Best CPU Cooler Performance

Overclockers and performance enthusiasts both share the same desire to cool their processor with the best possible hardware solution, but they each have different needs. The Benchmark Reviews test lab is rife with cooling products, ranging from silent low-profile to full-size tower coolers. The purpose of this series is to measure products for the best cooling performance in both stock and overclocked forms. In this article, Benchmark Reviews tests a new collection of LGA1366 coolers against a set of battle-proven products like the Prolimatech Megahalems, Xigmatek Thor's Hammer, and Thermalright TRUE, in search of the Best CPU Cooler Performance LGA1366 Q3 - 2009. Unlike the last quarterly report, there's a new name for enthusiasts and overclockers to remember in this roundup.

When it comes down to it, those consumers shopping for aftermarket cooling products only want one thing out of them: the very best cooling performance possible. Short of dangerous dry ice and liquid nitrogen (LN) cooling, air cooling has become the most popular means to control overclocked processor temperatures. Since new products flood the market almost weekly, it usually all comes down to price and performance. Based on this principle, Benchmark Reviews searches out the latest CPU coolers and tests them under real-world overclocked conditions. Want to know which cooling products stand-out? This quarterly update to our Best CPU Cooler Performance series will separate the good from the bad... but we also find those products that are truly exceptional and deserving of your high-power hardware projects.

Using the Intel Core i7-920 processor overclocked to 3.8 GHz @ 1.4V on the Gigabyte GA-EX58-EXTREME motherboard, only the very best CPU coolers will endure. Alternatively, for casual hardware enthusiasts we use the 2.66 GHz i7-920 at stock voltage and test product performance out of the box. Comparing the ranking between test segments, our benchmarks results should reveal the most desirable heatsink for your computer system.

Benchmark Reviews strives to offer the overclocker and hardware enthusiast community solid evidence reflecting the true performance of computer products through rigorous testing and evaluation. I personally understand that many of the readers who visit Benchmark Reviews have been involved with other community websites for several years, and therefore take our test results personally. So now that our test process has been reworked, we have collected the most complete source of benchmark results possible and gathered in a controlled environment. The purpose of this sixth article from our quarterly series is to document performance and declare the best CPU coolers available for the LGA1366 socket as of Q2 2009.

Before the Intel Core i7/X58 platform arrived, the Core 2 Duo and Core 2 Quad processors did their part to separate the cream of the crop from our large collection of LGA775 coolers. In a previous Best CPU Cooler Performance article, Benchmark Reviews retired the LGA775 platform from its testing duties and made room for the up-and-coming LGA1366 socket. It didn't take long to collect several CPU coolers designed for the Intel Core i7 CPU & X58 platform. This Best CPU Cooler Performance LGA1366 - Q3 2009 article focuses on a wide selection of performance-cooling products for overclockers. It's a mistake to think that any LGA775 cooler can do just as well with the new LGA1366/Core i7 platform; primarily because the size and location of processor cores has changed.

Computer hardware is an ever-evolving industry, and since Moores law only applies to an exponentially growing transistor count then there should probably be another law for cooling. In the very recent past there have been two major trends which have accelerated the performance potential of CPU cooler. That first development was the use of heat-pipes to directly contact with the CPU surface; which resulted in the Heat-pipe Direct Touch technology. The second development is by no mean a new concept, just new to our industry in specific. For many years now heatsinks have been full of right angles, but very recently companies have begun to recognize the need to disrupt smooth airflow and reduce the laminar skin effect which allows air to travel just above the solid surface. Some manufacturers have used at least one of these new concepts in their product design, and only a few are beginning to incorporate both. Benchmark Reviews will see how much this affects the overall performance as we test a large segment of enthusiast cooling products.

Before we inspect each member of our new CPU cooler collection, let's establish that our tests consist of methods we have determined to be the best for our one singular purpose. Our methodology isn't written in stone, and could very likely be changed or modified as we receive justification (and feedback from the community). Our scope is limited to stand-alone products only, meaning those products which can be installed and operated without additional critical components needed or kit construction. This generally excludes most commercial liquid cooling systems, which may potentially offer better performance than the products we test for this article but require components to be assembled from various options and equipment. Suffice it to say, the vast majority of gamers and enthusiasts are using air-cooled solutions and therefore we target this review series towards them. We encourage hardware enthusiasts to utilize the equipment available to them, and select the cooling fan that best suits their needs. Just keep in mind that exceptional cooling performance must begin with the CPU cooler, and end with the cooling fan. It's the foundation of the unit that makes a difference, which is exactly what we're after in this article.

EDITOR'S NOTE 13 FEB 2010: Benchmark Reviews will publish our Q1-2010 Best CPU Cooler Performance LGA1366 article on 11 March 2010. Several new heatsinks along with some enthusiast favorites will all be tested on an overclocked six-core processor. Additionally, our performance test results for the AMD AM3 socket will also be included.

Conductive Elements

Manufacturers have made a small fortune off of confusion tactics and misinformation. Marketing departments often times neglect to refer back to solid science when making their bold claims, which is why we have assembled a complete list of thermally conductive elements in the reference chart below.

It's very well known that Silver, Copper, Gold, and Aluminum together comprise the top four most thermally conductive elements. However, without knowing the thermal conductance of these elements you might be fooled into thinking the performance was close. As it turns out, Silver and Copper both offer nearly twice the performance of Aluminum when transferring thermal energy such as heat. The reason Aluminum is used in so many applications is because it's the least expensive top-tier metal available. Most Thermal Interface Material and CPU coolers use several different elemental ingredients to work together, but after a careful inspection of the performance levels it comes as a surprise to me that some of the most popular products make use of such poor conductive elements.

Recipes usually call for only the finest ingredients, and the very same principle is true for overclocker and hardware enthusiast products. Thermal pastes are often times mixed from at least a dozen different components, while heatsink coolers may use only one or two different metals. Armed with the knowledge above, you might expect any silver-based product to be a clear-cut winner... but building a superior product by design is different than what you receive in execution. Production and material costs usually dictate how the product is designed and fabricated.

Keep these materials in mind as we take a look at the new products Benchmark Reviews has collected for this round-up article, beginning with our first contender...

Cogage TRUE Spirit

Cogage is the brand name for mainstream Thermalright products, and the name stands for Computer and Gaming Gear. The Cogage TRUE Spirit is a more-affordable version of the extremely popular Thermalright Ultra-120 eXtreme CPU cooler. Both products share the same mounting clip system and base design, but the TRUE Spirit offers only four heat-pipe rods instead of six. Other differences include a light-weight design, reducing the original TRUE (16cm H x 13.2 W x 6.3 L) into the TRUE Spirit (16cm H x 13.2 W x 5.3 L). Overall the Cogage TRUE Spirit closely resembles the Ultra-120 eXtreme, right down to the 58 aluminum bent-winglet fins.

The Cogage TRUE Spirit kit Benchmark Reviews received for testing came with a 120mm cooling fan and traditional Intel push-pin style mounting clip system. Cogage was kind enough to also include the aftermarket LGA1366 Bolt-Thru-Kit by Thermalright (UPC 814256-00079), which was utilized for all tests on the TRUE Spirit as well as the Ultra-120 eXtreme. While the included push-pin mounting system is adequate at best, the aftermarket kit worked extremely well and shared a similar design to the Prolimatech Megahalems. As of October 2009 the Cogage TRUE Spirit was available at FrozenCPU for $39.95.

TRUE Spirit Features

• Quiet and powerful cooling due to multiple heat pipes and large fin area
• Supports all clock Core i7
• Proprietary Bent Winglet design to minimize airflow resistance
• Utilizes 4 high quality 6mm heatpipes, strategically positioned to pick up the heat from the CPU
• Stack of 48 Pieces of aluminum fins, can be covered entirely by a 120mm fan to absorb all in-coming air flow
• Includes PWM Control 120mm x 25mm Fan

CPU-TRI-62 Specifications

• Cooler Dimensions: 133 x 156 x 38 (L x W x H)
• Cooler Weight: 670 g
• Heatpipes: Four
• Fan Dimensions: 120 x 120 x 25 mm
• Fan Rated Speed: 1000 - 1500 RPM (±15%)
• Fan Noise Level: 19.6 - 37.4 dBA
• Fan Air Flow: 35.0 - 66.5 CFM

About Thermalright, Inc.

Cogage is the brand name for mainstream Thermalright products, and the name stands for Computer and Gaming Gear.

Thermalright is an elite design house that manufactures cooling products for computer components for the best quality and performance your money can buy. In 2002, AMD released its first generation Thunderbird CPU and since then we have been there every step of the way to counter high voltage and high heat with innovative design and highly acclaimed cooling solutions not only for AMD but for Intel as well. One of early well known solutions was the SK-6. With many positive and rave reviews under its belt Thermalright bolted to the top as the heat sink manufacturer mostly preferred by Overclockers and enthusiasts around the World. To this day, innovation never left our vocabulary as we keep coming up with leading edge designs staying ahead of the competition.

CoolAge CA-X120TF Wind Tunnel

CoolAge is a lesser-know name to North American markets, but that shouldn't mean that their products don't deserve the utmost attention. Taking one look at the X120TF 'Wind Tunnel' cooler, and you'll notice some of the traits that make CPU coolers great. A very dense weave of aluminum fins create the most complete heatsink we've seen a long time, only made better by six offset and staggered heat-pipe rods bent into the traditional 'U' tower design. CoolAge nicknames the CA-X120TF model 'Wind Tunnel' for the crimped fin plates which create a larger surface area using honeycombs for air to pass through.

The X120TF kit came with more than enough enthusiast hardware to convince us that CoolAge knows what they're doing. A high-pressure bolt-through mounting kit comes stock with the CoolAge X120TF, along with a large syringe of CA-TC3 Nano thermal paste. While the CA-X120TF kit doesn't include a cooling fan, CoolAge was kind enough to include their CA-120SX2 cooling fan, which measures 120x120x38mm. For the record, Benchmark Reviews tests stock performance using the Scythe Kaze-Jyuni SY1225SL12SH for all coolers that lack their own included fan.

The CoolAge CA-X120TF features six heat-pipe rods configured in a traditional 'U' tower design. One particular stand-out feature is the staggered positioning of each rod, arranged so that all twelve heat-pipe ends receive fresh incoming air. A polished heatsink base receives all six heat-pipe rods, which are soldiered into the unit for maximum thermal conductivity. The bolt-through mounting system applies excellent pressure between contact surfaces, although access to the backside of the motherboard is required for installation. Benchmark Reviews will soon discover is this cooler from the CoolAge Frozen Orb series performs as well as it looks.

CoolAge CA-X120TF Specifications

• Product Name: Frozen Orb X120 Transform
• Model Number: CA-X120TF
• Dimensions: 126(W) x 63(D) x 150(H) mm
• Weight: 750g
• Heatsink Base Material: Copper
• Heatsink Fin Material: Aluminum Alloy
• Heat-pipes: six 6mm copper rods

About Hilo Company, Ltd

CoolAge is a division of Hilo Company, Ltd. CoolAge is a Seoul, Korea based brand name that focuses on enthusiast computer hardware. CoolAge operates with a focus on the overclocker cooling market and aftermarket cooling systems. For more information, visit the CoolAge website at www.coolage.co.kr

Corsair H50 CWCH50

Corsair has enjoyed a strong name among overclockers because of their system memory products, but in the past year the product line has extended to Solid State Drives, computer cases, and CPU coolers. Many of Corsairs latest cooling products call upon designs from Asetek as the OEM. The Corsair H50 (model CWCH50) utilizes the Asetek LCLC cooling unit, and offers overclockers with a silent-running cooling solution for the performance computer system.

The Corsair H50 kit Includes mounting brackets for only the Intel LGA775 and LGA1366 socket motherboards. However, brackets for AMD socket AM2 and AM3 motherboards are available for a nominal shipping and handling charge by contacting Corsair Technical Support. The Corsair H50 CWCH50 kit is currently available at FrozenCPU and NewEgg for around $90.

Corsair H50 Features

• Pre-filled, closed-loop system is easy to install
• Copper CPU cooling plate for maximum cooling performance
• Integrated pump and reservoir is sealed for zero maintenance and improved leakage protection
• Large 120mm radiator for fast heat dispersion
• High-efficiency, low-noise 120mm fan for drawing cool air across the radiator
• Two-year warranty

The Corsair H50 comes with pre-applied thermal compound, which spreads when contact pressure and heat are applied. The mounting system is comprised of a bolt-through retaining clip that mounts to a metal motherboard backplate, and is tightened once the waterblock is fitted beneath the retaining ring. Our installation of the CWCH50 kit on the Intel LGA1366 was very simple and straight-forward, although access to the backside of the motherboard is required.

CWCH50 Specifications

About Corsair Memory Inc

Founded in 1994, Corsair Memory, Inc., is a worldwide leader in high-performance components for personal computers. Specializing in very high performance memory and ultra-efficient power supplies, our flagship products, Including Dominator memory modules, are the choice of overclockers, enthusiasts, and gamers everywhere. Our expertise in design and manufacturing is also evident in our complete line of Flash Voyager and Flash Survivor USB storage devices. Corsair offers 24/7 customer support via forums and the Tech Support Express helpdesk. For more information, please visit www.corsair.com

Scythe Kabuto SCKBT-1000

So many of today's aftermarket cooling solutions have adopted the 'U' tower design for their products that it's become a rare occasion to see a CPU cooler break the mold. The Scythe Kabuto cooler uses an included 120mm Slip-Stream 1300RPM fan, which is great for moderate airflow with minimal noise. Because of the large footprint, the Scythe Kabuto is relegated to using the stock Intel push-pin style clip mounting system. While this doesn't provide the best contact pressure, it does allow installation without removing the motherboard.

The Scythe Kabuto SCKBT-1000 is really one heatsink atop another, with a solid aluminum heatsink venting up from the base and connected to the large aluminum finsink by six large-gauge heatpipe rods. As of October 2009, the Scythe Kabuto SCKBT-1000 kit is available at NewEgg for $44.99.

Scythe Kabuto Features

• Top Mount Fan
  The Slip Stream 120 mm PWM fan mounted on top of the cooler is suited both to transport the heat of the CPU cooler away and to cool down sensitive components of the mainboard.
• M.A.P.S. (Multiple Pass-Through Airflow Structure)
  The newly developed M.A.P.S. (Multiple Airflow pass-through structure) is a completely new fin structure, where the airflow generated by the Scythe Slip Stream 120 mm PWM fan can be used perfectly.
• 4-Way Mounting
  By orientating the fixing holes of the mounting clips in a square, users can mount the heatsink in four different ways.

SCKBT-1000 Specifications

About Scythe USA

So who is Scythe? What do they do? Many of you are asking this question while surfing our website. Scythe Co., Ltd. (Registered & incorporated in Tokyo Japan) originally started in Akihabara Electric Town located in Tokyo Japan, where visitors can find the latest electric products from computer parts and accessories to the world's most advanced cellular phones with video camera capabilities, small displays and the ability to play movies!

Scythe Co., Ltd., began its operation and business in November, 2002 as a distributor and manufacture of PC parts & gaming devices for "DIY PC Experts!". For more information about Scythe Japan HQ, please visit the website at: www.scythe.co.jp (If you read Japanese!). Scythe's first venture was to manufacture a super powerful YET super quiet CPU cooler (Scythe Kamakaze CPU cooler), and with the great success of this Kamakaze CPU cooler, Scythe became recognized as the leading CPU cooler supplier in Japan's Akihabara Electric Town. Shortly there after, due to popular demand, Scythe began exporting products all over the world.

In April of 2004 Scythe USA began local operations by establishing an office in Northern California. In October of 2004 Scythe USA moved operations to LA in order to work more closely with manufactures and streamline logistics to better service our US based partners. Have you seen/heard anything interesting, from Japan's Akihabara electric town that you'd like us to import to the US? Let us know! We'd love to hear from you!

Scythe Mugen 2 SCMG-2000

Scythe has been a premium brand name in the aftermarket cooling industry for many years now, and has earned a reputation among enthusiast and overclockers for their giant-sized cooling solutions. The Scythe Mugen 2 is one of the largest air-cooled heatsinks Benchmark Reviews has tested... at least since the original Scythe Mugen Infinity project. Aside from splitting the heatsink into five smaller groups of fins, these two coolers share almost identical design.

The Scythe Mugen 2 includes a single Scythe Slip-Stream cooling fan, but the large SCMG-2000 unit can accommodate two 120mm cooling fans total (presuming the enclosure will support the area needed). Although the Mugen 2 utilizes a high-pressure bolt-through mounting system, the entire LGA1366 socket assembly needed to be removed in order to facilitate heatsink installation.

Similar to other Scythe coolers, the Mugen-II SCMG-2000 is really one heatsink atop another. A solid aluminum heatsink venting up from the base is connected by five large-gauge heatpipe rods to a group of five aluminum finsinks. Each finsink segment helps to separate the heat-pipe rods, and isolate heat distribution. How effective this concept is over the previous design will soon be revealed. The Scythe Mugen 2 SCMG-2000 kit is available at NewEgg for $34.99.

EDITOR'S NOTE: The Scythe Mugen-2 Revision B model SCMG-2100 heatsink is identical to the first version, model SCMG-2000. The only difference is that Mugen-2 Rev. B uses a newly developed F.M.S.B. (Flip Mount Super Back-Plate) for more convenient mounting onto the motherboard. There should not be any cooling performance between these two models, despite marketing hype.

Long expected and now finally here: Scythe Mugen 2 CPU cooler is the consistent further development of the award-winning Mugen CPU cooler. Several features make this cooler the perfect solution for silent users and overclockers! In a nearly 1-year development period, the concept of Mugen was completely revised and further developed. Mugen 2 is on the latest state of technology and was produced using highest Japanese quality standards.

Scythe Mugen 2 Features

• F.M.S.B. (Flip Mount Super Back-Plate)
  The newly developed F.M.S.B. (Flip Mount Super Back-Plate) both improves the compatibility and mounting of the cooler with the motherboard. With this system, a solution was developed which is not using push pins but is instead based on a Back Plate/screws mounting set. Of course, Mugen 2 is compatible with all the current sockets, including the new Intel Socket LGA1366.
• Multi Fan Mount Structure
  As with the former Mugen it is possible to mount the supplied fan in four different directions. By this, the user can arrange the air flow to the circumstances of his deployment area. Furthermore, a maximum of 4 fans be installed, the needed fan clips have to be bought separately.
• M.A.P.S. (Multiple Airflow Pass-Through Structure)
  The newly developed M.A.P.S. (Multiple Airflow pass-through structure) is a completely new lamellar structure, where the airflow generated by the Scythe Slip Stream 120 mm PWM fan can be used perfectly

SCMG-2000 Specifications

About Scythe USA

So who is Scythe? What do they do? Many of you are asking this question while surfing our website. Scythe Co., Ltd. (Registered & incorporated in Tokyo Japan) originally started in Akihabara Electric Town located in Tokyo Japan, where visitors can find the latest electric products from computer parts and accessories to the world's most advanced cellular phones with video camera capabilities, small displays and the ability to play movies!

Scythe Co., Ltd., began its operation and business in November, 2002 as a distributor and manufacture of PC parts & gaming devices for "DIY PC Experts!". For more information about Scythe Japan HQ, please visit the website at: www.scythe.co.jp (If you read Japanese!). Scythe's first venture was to manufacture a super powerful YET super quiet CPU cooler (Scythe Kamakaze CPU cooler), and with the great success of this Kamakaze CPU cooler, Scythe became recognized as the leading CPU cooler supplier in Japan's Akihabara Electric Town. Shortly there after, due to popular demand, Scythe began exporting products all over the world.

In April of 2004 Scythe USA began local operations by establishing an office in Northern California. In October of 2004 Scythe USA moved operations to LA in order to work more closely with manufactures and streamline logistics to better service our US based partners. Have you seen/heard anything interesting, from Japan's Akihabara electric town that you'd like us to import to the US? Let us know! We'd love to hear from you!

Tuniq Tower-120 Extreme

Most overclockers still consider the original Tuniq Tower 120 CPU cooler to be a fan favorite, which is exactly why Sunbeamtech has introduced its successor: the Tuniq Tower 120 Extreme. While the CR-T120-EX-BK kit offers several improvements over the previous design, there's no getting around motherboard removal to install the Tuniq Tower 120 Extreme because of the tight fitting thumb-screws that must be secured under the heatsink.

As of October 2009, the Tuniq Tower 120 Extreme is available from FrozenCPU for $64.99.

The performance king has returned! The much praised Tuniq Tower 120 has gone through a radical redesign and not only looks cooler but its performance has been boosted. The unique wave-like fins display a tremendous visual impact and increase the air-contact area for an unprecedented thermal performance. The nickel-plated surface combined with the LED fan creates a breath taking visual effect!

To ensure that the maximum cooling performance is obtained, we have also included our highest performing thermal compound, the TX-3. Furthermore, our unique adjustable fan controller places the control in your hands!

Tower 120 Extreme Features

• Three High Performance 8mm and two High Performance 6mm U-shaped Heat-pipes
• Silent 120mm MFDB Fan (Magnetic Fluid Dynamic Bearing)
• Includes TX-3 Thermal Grease (0.33ml/1g)
• Heat-pipe Direct Touch 'Core Contact' Design

About Tuniq Co., Ltd.

Tuniq was formed as a division of Sunbeamtech and took on a whole new direction in product designs. We at Tuniq aim to provide authentic performance through a minimalist approach by stripping down the unnecessary components in product designs. Our research and development team consists of members who have over a decade of experience as well as young designers who are able to think outside of the box. It is this unique merge of experience and fresh ideas that enables us to bring to our customers such exquisite, elegant, top-quality products.

We feel that product design should be Zen-like: simple, functional, harmonious and without frails. Each product from Tuniq aims to combine the virtues of high performance, elegant design, and extraordinary value. When handling a Tuniq product, you will appreciate its impeccable finish and will be pleasantly amazed by its quality and performance.

With the multitude of awards and acclaims that each of our products has received, we have proven that our vision and approach is the right one and we will continue to provide our valued customers with new and better products.

ZEROtherm Nirvana NV120 PWM Premium

The ZEROtherm Nirvana NV120 Premium is the embodiment of everything effective from cooler designs, taking only what works and combining it into a package product that tames the most unique hardcore system. The Apack ZEROtherm Nirvana NV120 Premium is identical to the Nirvana NV120 PWM, sharing identical construction and design. Aluminum fins surround the sides of an embedded 120mm fan, and the uneven pattern of each aluminum fin plate creates a Honeycomb structure for optimized air flow. Four heat-pipe rods span from up in a traditional 'U' tower design, with each of the four heat-pipe ends running directly behind the airflow path of the next. The fan uses the Pulse-Width Modulation (PWM) to control rotational speed, and operates between 900-1800RPM.

The ZEROTherm NV120 features a bolt-through mounting clip system, which fits all Intel LGA775/LGA1366 sockets, as well as AMD 939/940/AM2?AM2+/AM3 sockets. The ZEROTherm website claims that the Nirvana NV120 is not compatible with Intel 1156/478/771/603/604 and AMD Socket 754/F/A motherboards, which is unfortunate for legacy hardware users. As of October 2009 the ZEROtherm Nirvana NV120 was available at NewEgg for $49.99.

ZEROtherm Nirvana Features

• Effective 8-line Heat-pipe design
• Honeycomb structure for optimized air flow. More than 6,748 §² heat dissipation area
• 120mm fan for max. air-flow (up to 84.7 CFM)
• Manual fan speed Controller Adapted
• Polished NI-Plated Copper Base
• Supports Latest Intel & AMD CPUs

NV120 PWM Specifications

About Apack, Inc.

ZEROTherm is the cooling product brand name owned by APack, Inc.

The name ZEROTherm was christened by Dr. Song, our CEO and lifelong engineer. For our first product he said, "With our first retail product we need exceed expectations, so make it happen." While ZEROTherm represented our engineering goal to build a competitive cooler, our design point was that we were to use our first product as a "first flight" into the retail market. Of course, we've done one-of-a-kind thermal cooling solutions that had exact specs to meet and restrictions to consider, so we wanted to include a design that expressed our own craftsmanship as well.

So the butterfly design was to be incorporated into our first product because it represents our first flight into the retail market, but also like a butterfly, our company APACK was changing from a very comfortable OEM market to the very open world-wide market.

Of course every product can be better and it's something that we are working hard on, but maybe people will not understand the butterfly design or be critical of it. But for us, it was part of an effort to show our ability in design as well as in engineering. We hope that all ZEROtherm products can show our commitment to engineering value in price, design and performance. ZEROtherm is committed to try everyday not to just meet your expectations, but to put all our efforts into exceeding them.

Surface Preparation

Processor and CPU cooler surfaces are not perfectly smooth and flat surfaces, and although some surfaces appear polished to the naked eye, under a microscope the imperfections become clearly visible. As a result, when two objects are pressed together, contact is only made between a finite number of points separated by relatively large gaps. Since the actual contact area is reduced by these gaps, they create additional resistance for the transfer of thermal energy (heat). The gasses/fluids filling these gaps may largely influence the total heat flow across the surface, and then have an adverse affect on cooling performance as a result.

Surface Finish Impact

CPU coolers primarily depend on two heat transfer methods: conduction and convection. This being the case, we'll concentrate our attention towards the topic of conduction as it relates to the mating surfaces between a heat source (the processor) and cooler. Because of their density, metals are the best conductors of thermal energy. As density decreases so does conduction, which relegates fluids to be naturally less conductive. So ideally the less fluid between metals, the better heat will transfer between them. Even less conductive than fluid is air, which then also means that you want even less of this between surfaces than fluid. Ultimately, the perfectly flat and well-polished surface is going to be preferred over the rougher and less even surface which required more TIM (fluid) to fill the gaps.

This is important to keep in mind, as the mounting surface of your average processor is relatively flat and smooth but not perfect. Even more important is the surface of your particular CPU cooler, which might range from a polished mirror finish to the absurdly rough or the more complex (such as Heat-Pipe Direct Touch). Surfaces with a mirror finish can always be shined up a little brighter, and rough surfaces can be wet-sanded (lapped) down smooth and later polished, but Heat-pipe Direct Touch coolers require some extra attention.

To sum up this topic of surface finish and its impact on cooling, science teaches us that a smooth flat mating surface is the most ideal for CPU coolers. It is critically important to remove the presence of air from between the surfaces, and that using only enough Thermal Interface Material to fill-in the rough surface pits is going to provide the best results. In a perfect environment, your processor would mate together with the cooler and compress metal on metal with no thermal paste at all; but we don't live in perfect world and current manufacturing technology cannot provide for this ideal environment.

Mounting Pressure

Probably one of the most overlooked and disregarded factors involved with properly mounting the cooler onto any processor is the amount of contact pressure applied between the mating surfaces. Compression will often times reduce the amount of thermal compound needed between the cooler and processor, and allow a much larger metal to metal contact area which is more efficient than having fluid weaken the thermal conductance. The greater the contact pressure between elements, the better it will conduct thermal (heat) energy.

Unfortunately, it is often times not possible to get optimal pressure onto the CPU simply because of poor mounting designs used by the cooler manufacturers. Most enthusiasts shriek at the thought of using the push-pin style clips found on Intel's stock LGA775 thermal cooling solution. Although this mounting system is acceptable, there is still plenty of room for improvement.

Generally speaking, you do not want an excessive amount of pressure onto the processor as damage may result. In some cases, such as Heat-pipe Direct Touch technology, the exposed copper rod has been pressed into the metal mounting base and then leveled flat by a grinder. Because of the copper rod walls are made considerably thinner by this process, using a bolt-through mounting system could actually cause heat-pipe rod warping. Improper installation not withstanding, it is more ideal to have a very strong mounting system such as those which use a back plate behind the motherboard and a spring-loaded fastening system for tightening. The Noctua NH-U12P is an excellent example of such a design.

In all of the tests which follow, it is important to note that our experiments focus on the spread pattern of thermal paste under acceptable pressure thresholds using either a push-pin style mounting system or spring-loaded clip system. In most situations your results will be different than our own, since higher compression would result in a larger spread pattern and less thermal paste used. The lesson learned here is that high compression between the two contact surfaces is better, so long as the elements can handle the added pressure without damaging the components.

Thermal Paste Application

The entire reason for using Thermal Interface Material is to compensate for flaws in the surface and a lack of high-pressure contact between heat source and cooler, so the sections above are more critical to good performance than the application of TIM itself. This section offers a condensed version of our Best Thermal Paste Application Methods article.

After publishing our Thermal Interface Material articles, many enthusiasts argued that by spreading out the TIM with a latex glove (or finger cover) was not the best way to distribute the interface material. Most answers from both the professional reviewer industry as well as enthusiast community claim that you should use a single drop "about the size of a pea". Well, we tried that advice, and it turns out that maybe the community isn't as keen as they thought. The example image below is of a few frozen peas beside a small BB size drop of OCZ Freeze TIM. The image beside it is of the same cooler two hours later after we completed testing. If there was ever any real advice that applies to every situation, it would be that thermal paste isn't meant to separate the two surfaces but rather fill the microscopic pits where metal to metal contact isn't possible.

After discussing this topic with real industry experts who are much more informed of the process, they offered some specific advice that didn't appear to be a "one size fits all" answer:

1. CPU Cooling products which operate below the ambient room temperature (some Peltier and Thermo-electric coolers for example) should not use silicon-based materials because condensation may occur and accelerate compound separation.
2. All "white" style TIM's exhibit compound breakdown over time due to their thin viscosity and ceramic base (usually beryllium oxide, aluminum nitride and oxide, zinc oxide, and silicon dioxide). These interface materials should not be used from older "stale" stock without first mixing the material very well.
3. Thicker carbon and metal-based (usually aluminum-oxide) TIM's may benefit from several thermal cycles to establish a "cure" period which allows expanding and contracting surfaces to smooth out any inconsistencies and further level the material.

The more we researched this subject, the more we discovered that because there are so many different cooling solutions on the market it becomes impossible to give generalized advice to specific situations. Despite this, there is one single principle that holds true in every condition: Under perfect conditions the contact surfaces between the processor and cooler would be perfectly flat and not contain any microscopic pits, which would allow direct contact of metal on metal without any need for Thermal Interface Material. But since we don't have perfectly flat surfaces, Thermal Material must fill the tiny imperfections. Still, there's one rule to recognize: less is more.

Cooler Test Methodology

Benchmark Reviews has been obsessed with testing CPU coolers over the few years. We've solicited suggestions from the enthusiast community, and received guidance from some of the most technical overclockers on the planet. As a result, our testing methodology has changed with every edition of our Best CPU Cooler Performance series. Because of this, each article is really its own stand-alone product, and cannot be fairly compared to the others. This article is going to be a perfect example of that principle, although certain tenants still hold true. Benchmark Reviews continues to test CPU coolers using the stock included fan (whenever applicable), and then replaces it with a high-out fan for re-testing.

Manufacturers are not expected to enjoy this sort of comparison, since we level the playing field by replacing their included fan with a common unit which we then use for every CPU cooler we test. Manufacturers regularly include fans with their CPU cooler products, and more often than not these fans are very high RPM units which offer great airflow at the expense of an obnoxiously loud noise level. By using the same model of cooling fan throughout our testing, we can assure our results are comparable across the board. This is one of the more significant changes we have made to our test methodology, since many of the benchmark tests we have conducted in the past have compared the total package. Ultimately we're more interested in the discovering the best CPU cooler performance and we believe that you'll feel the same way.

Testing was conducted in a loosely scientific manner. Ambient room temperatures levels were held to within one degree of fluctuation measured at static point beside the test equipment with a calibrated digital thermometer. All coolers had their original manufacturer-supplied thermal material removed and replaced with a product of our choosing listed in the support equipment section below. Each product then received the same amount of Thermal Interface Material (specified below), which amounted to roughly a BB-sized drop placed onto the center of the CPU. The CPU cooler product being tested was then laid down flat onto the CPU, and compressed to the motherboard using the supplied retaining mechanism. If the mounting mechanism used only two point of force, they were tightened in alternation; standard clip-style mounting with four securing points were compressed using the cross-over method. Once installed, the system was tested for a baseline reading prior to testing.

At the start of each test, the ambient room temperature was measured to track any fluctuation throughout the testing period. EVEREST Ultimate Edition v5.02.1750 by Lavalys was then utilized to create core loads and measure each individual CPU core temperature. It's important to note that software-based temperature reading reflects the thermal output as reported from the CPU to the BIOS. For this reason, it is critically important (for us) to use the exact same software and BIOS versions throughout the entire test cycle, or the results will be incomparable. All of the units compared in our results were tested on the same motherboard using the same BIOS and software, with only the product itself changing in each test. These readings are neither absolute nor calibrated, since every BIOS is programmed differently. Nevertheless, all results are still comparable and relative to each products in our test bed.

One unfortunate problem is that CPU's report temperatures as a whole number and not in fractions. This in turn causes the motherboard BIOS and subsequent software applications such as EVEREST to also receive whole-number reports. Thankfully, EVEREST also does offer averages in the statistics panel, which gives us more precise readings. To further compensate for this, our tests were conducted several times after complete power down thermal cycles. Conversely, the ambient room temperature levels were all recorded and accurate to one-tenth of a degree Celsius at the time of data collection.

When each cooler is tested, Benchmark Reviews makes certain to keep the hardware settings identical across the test platform. This enables us to clearly compare the performance of each product under identical conditions. While the ambient room temperature did fluctuate between 21~22°C during testing, this would not be enough to impact our test results since only the thermal difference is reflected in the charts. For the purpose of this article, thermal difference (not the same as thermal delta) is calculated by subtracting the ambient room temperature from the recorded CPU temperature.

Test System

• Motherboard: Gigabyte GA-EX58-EXTREME (Intel X58/ICH10R Chipset)
• Processor: Intel Core i7-920 BX80601920 2.66 GHz (overclocked to 3.80 GHz @ 1.40V)
• System Memory: OCZ 6GB 1600MHz CL7 DDR3 OCZ3P1600LV6GK
• System Drive: OCZ Vertex 120GB SATA SSD OCZSSD2-1VTX120G
• Optical Drive: ASUS BC-06B1ST Blu-Ray Disc Optical Combo Drive
• Enclosure: Cooler Master ATCS 840 Computer Case RC-840
• PSU: Antec TruePower Quattro 850W TPQ-850
• Grpahics: ZOTAC GeForce 9800 GTX+ Zone Edition (liquid cooling looped into X58 Northbridge)
• Operating System: Windows XP Professional SP-3 (optimized to 16 processes at idle)

Support Equipment

• EVEREST Ultimate Edition v5.02.1750 by Lavalys
• Tuniq TX-3 (No curing time necessary or given)
• Scythe Kaze-Jyuni 120x120x25mm fan, model SY1225SL12SH (110.31 CFM Advertised @ 37.0 dBA) 12V/0.53A
• Yate Loon 120x120x25mm fan, model D12SH-12 (88 CFM Advertised @ 40 dBA) 12V/0.30A
• Scythe Ultra Kaze 120x120x38mm fan, model DFS123812H-3000 (133.6 CFM Advertised @ 45.9 dBA) 12V/0.60A
• CoolAge SX2 120x120x38mm fan, model CA-120SX2 (80 CFM Advertised @ 32 dBA) 12V/0.19A
• Xigmatek CrossBow ACK-I7361 (supports xxxx1 / xxxx2 / xxxx3 cooler models)
• Xigmatek CrossBow ACK-I7363 (supports xxxx4 / xxxx5 / xxxx6 cooler models)
• Thermalright LGA1366 Bolt-Thru-Kit UPC 814256-00079 (supports all TRUE and TRUE Spirit models)

All of our tests are now conducted using only the vertical motherboard orientations traditional to tower computer systems. At the start of our test period, the test system is powered on and EVEREST system stability tests are started with Stress CPU and Stress FPU options selected. For a minimum of sixty minutes (one hour) EVEREST loads each CPU core to 100% usage, which drives the temperature to its highest point. Finally, once temperatures have sustained a plateau, the ending ambient room temperature and individual CPU core levels are recorded thus completing the first benchmark segment.

The second test segment involves removing the stock cooling fan (while the system is still under load) and replacing it with a high-output 120 mm Yate Loon D12SH-12 cooling fan. The system is given thirty additional minutes with EVEREST loading the CPU cores before final temperature readings are taken and recorded. Once the testing has been completed at the stock processor speed, Benchmark Reviews turns up the voltage on our Core i7-920 processor and overclocks to 3.8 GHz using a 1.40V vCore. When the system restarts, we start our testing over from the beginning and allow a minimum of sixty minutes of loading before taking our readings.

The Accuracy Myth

All modern processors incorporate an internal thermal diode that can be read by the motherboards' BIOS. While this diode and the motherboard are not calibrated and therefore may not display the actual true temperature, the error is constant. This means that if the diode reports 40°C when it is actually 43°C, then it will also report 60°C when it is truly 63°C. Since the design goal of a thermal solution is to keep the CPU core within allowable temperatures, a processor's internal diode is the most valid means of comparison between different heatsinks, or thermal compounds. The diode and motherboard may be incorrect by a small margin in relation to an actual calibrated temperature sensor, but they will be consistent in their margin of error every time.

Stock Cooling Fan Results

Benchmark Reviews tries to cover every angle, but sometimes it's just not possible given our time constraints. Past articles from our 'Best CPU Cooler Performance' series have largely focused on the Intel Core 2 Duo/Quad LGA775 socket, and while the results are relevant to users owning that series of processor, the new Core i7 platform is completely different. To the inexperienced enthusiast, a top-performing LGA775 cooler might be (mistakenly) considered worthy for cooling a new LGA1366 Core i7 project. This would be a grave error, because not only are the two processors different in overall size, they also place the processor cores in different locations. Simply stated: what worked well on a Core 2 platform may not work very good at all with Core i7.

When it comes to personal computers, you could probably divide users into two separate groups for almost any one topic. This article is no different, and those two groups include both enthusiasts and overclockers. Hardcore overclockers and serious hardware enthusiasts may not consider the stock cooling results very interesting, but they're welcome to skip ahead into the next section where we add a high-performance fan and then add overclocked values. Believe it or not though, some people are on a budget and don't have the extra money to spend on aftermarket cooling fans or an additional bolt-through mounting kit; sometimes they just want good cooling right out of the box. This section is for them.

In regards to fan noise, there are those of us who want it quiet while other will tolerate an eardrum-ringing whine. Since noise is a problem and not a solution, I believe that most enthusiasts want as much performance as they can get without additional tweaking and time-intensive modifications. That's what this test section is all about: how the cooler performs out of the box. For the "Stock Cooling Fan" results, Benchmark Reviews tests our collection of LGA1366 CPU coolers for this article using the following criteria: Each cooler is tested with the manufacturer-included fan, so that performance will be relevant to consumers using the product in stock form. For coolers that do not come with a fan, we used the Scythe Kaze-Jyuni 120x120x25mm fan, model SY1225SL12SH (110.31 CFM Advertised @ 37.0 dBA) 12V/0.53A.

Please keep in mind that a product that finishes at the top of the stock fan list isn't going to matter if you plan on overclocking your processor or invest in a different cooling fan. Manufacturer-supplied stock cooling fans usually offer either extremely high airflow or incredibly low noise, so there's a lot riding on what's packaged with the kit. Sure, there's added importance on the cooler's design and construction, but at the stock level these factors really don't carry tremendous weight. Here's how they measure out:

Benchmark Reviews has tested several new products (along with a few top-performers from the previous series) in stock form for the LGA1366 socket results charted above. The performance results position the coolers in the following order, with the temperature difference noted (CPU core temp minus ambient room temp) beside them:

Just as it had done in previous articles, the Scythe Kaze-Jyuni equipped Prolimatech Megahalems once again proves itself dominant over the entire collection of LGA1366 coolers recording 24.9°C over ambient. But let's be honest with ourselves here: not many people are really going to pay $65 (plus the cost of fans) to cool a stock processor. The Thermalright Ultra-120 eXtreme (with Scythe Kaze-Jyuni Slip-Stream fan) is in the same situation, offering excellent performance yet demanding a steep enthusiast package price. At the more affordable $39.95 price point, the Cogage TRUE Spirit is getting closer to reality for most mainstream enthusiasts and it performs right along side the biggest names. The Scythe Mugen 2, a cooler with twice the heft, also offers great stock performance for only $34.99. Next was the Titan FINRIR TTC-NK85TZ and Thermolab BARAM, both of which are relatively impossibly to purchase in North America. Although the dense fins do best with a high-output fan, the Xigmatek Thor's Hammer S126384 performed did very well when a silent-running Scythe Slip-Stream fan was attached.

Since the Corsair H50 CWCH50 liquid-cooling system operates at one single fan speed full-time, there's no way to tone-down noise for low-stress quiet-time usage. The $90 Corsair H50 managed temperatures down to 29.3°C over ambient at full load, which was only slightly better than the CoolAge FO-X120TF Wind Tunnel or the Kingwin XT-1264 cooler which costs $34.99. The Scythe Kabuto SCKBT-1000 did very well for itself, coming in ahead of the massive Tuniq Tower 120 Extreme and well-known Xigmatek HDT-S1283 that 30.1°C over ambient.

Less impressive was the ZEROtherm Nirvana NV120 PWM Premium that allowed temperatures of 33.5°C over ambient, which is a little too close to the stock Intel LGA1366 thermal solution that produced 38.5°C over ambient at full load. Without the ability to replace the integrated fan with another, it appears the NV120 offers less function than fashion. If you want to see how all of these coolers performed under full load and with a high-volume cooling fan attached, please continue into the next section.

Overclocked Cooling Results

Overclockers are known for being particular to their equipment, which is why Benchmark Reviews changes our format with each new project. Although it's impossible to nail-down which fan is the overwhelming choice for overclocker project, most enthusiasts would agree that the higher the airflow the more appropriate the fan. Because of size and design constraints in most of these products, a 120x120x25mm fan is as large as we can go with our collection of CPU coolers. This section uses the high-output Yate Loon D12SH-12 cooling fan on each product tested. The D12SH-12 cooling fan forces an impressive 88 CFM of air at a moderately noisy 40 dBA, and performs better than several 120x120x38mm fans we've tested (more on that later). In my experience, the Yate Loon D12SH-12 is one of the best 120mm cooling fans available in regards to the noise to performance ratio. Overclocked to 3.80Hz, Benchmark Reviews uses a lapped and polished Intel Core i7-920 CPU with 1.40V applied to the processor's vCore for this section.

While our stock performance tests use a standard Intel Core i7-920 Processor BX80601920 retail part, this section makes use of another Core i7-920 2.66GHz processor lapped flat with super-fine 1200 grid wet-sanding paper on a thick piece of glass. Once the Integrated Heat Spreader (IHS) exposed the copper finish, we switched to ultra-fine 2000 grit wet-sanding paper. To add a final buffing finish, the surface was wet-sanded with ultra-fine 2500 grit and then polished with liquid finishers. When the lapped Core i7-920 was reinstalled into the X58 test platform, the voltage was raised to 1.40V and pushed to a modest 3.80 GHz overclock. While some enthusiasts have dared to trespass beyond this voltage, Benchmark Reviews needed our test system to remain functional long enough to complete testing on nearly twenty various products under several different conditions. Our readers must remember that every product must pass testing on the same motherboard and processor, or the testing must be redone completely (which happened anyway, thanks to a failed motherboard).

All of the top performing CPU coolers have a few things in common: bolt-through mounting clip systems that create impressive contact pressure. Although some mounting systems are better designed than others, it's without a doubt that the Intel push-pin style of mounting clip is designed to provide adequate compression while offering the best installation convenience. The mounting system on the Prolimatech Megahalems uses an excellent bolt-through system with slotted alloy plates to ensure a perfectly centered cooler, which was a good bit better than the Xigmatek Crossbow kits we use on compatible coolers. The Thermalright Ultra-120 eXtreme and Cogage TRUE Spirit also use a similar bolt-through kit... so contact pressure is extremely high for all of these coolers. At least half of our CPU cooler collection have very flat mirror-finished contact surfaces, whereas the other half use Heat-pipe Direct Touch (HDT) technology. Every single one of these coolers have either large-gauge heat-pipes, or several pairs of heat-pipe rods integrated into the base. In my opinion nearly every single product on this chart is an outstanding aftermarket cooler, but only a select few can be considered the very best. Charted below, Benchmark Reviews reveals the the results of our LGA1366 CPU cooler performance tests:

The overclocked Intel Core i7-920 processor really helped to separate the performance between products, especially at 1.40V vCore. Our large sixteen-unit collection of LGA1366 cooler varied by more than 18°C between them. Benchmark Reviews is confident that these results match those by enthusiasts with identical system hardware and configuration, however because our tests utilize a water-cooled video card and X58-Express Northbridge to avoid nearby heat transfer into our results, your own results will be slightly higher.

The added voltage and overclock immediately increased the core temperatures by 20°C, and is not recommended for coolers with stock fans, Even with the high-output Yate Loon D12SH-12 the temperatures climbed. All kits tested here used either an included or aftermarket bolt-through kit for mounting the cooler and creating optimal contact pressure. After each test run was completed (one hour), the cooler was removed and the thermal paste contact spread was inspected before being cleaned and re-installed for another test. Doing this revealed an peculiar trend, which make the distinction between LGA775 and LGA1366 performance more understandable.

Because of the slightly spread-out core placement on a Core 2 Quad or Duo processor, most 6mm triple heat-piped HDT cooler would make directly-aligned contact with the cores through the IHS. However, when it comes to the Core i7 series the processor cores line-up better with four-piped HDT coolers (or at the outer edge of the center heat-pipe in the three-piped HDT cooler). Conversely, coolers with a solid base are not effected by either platform, so long as they're big enough to saturate the contact surface. Making matters a little more complicated is the orientation of the Core i7 processor series, which is restricted to comply with the Intel-designed horizontally-aligned rectangle shape (not square like LGA775 processors). The 32mm tall by 35mm wide Core i7 processor is more sensitive to how a cooler is mounted to it, and care must be take to ensure the IHS is fully covered by the heatsink.

Listed in their order of overclocked cooling performance, these are the Best CPU Coolers for the overclocked LGA1366 Core i7 platform for Q3 2009. Please note that the thermal difference (CPU core temps subtracted from the ambient room temp) is listed beside each CPU cooler:

For the first time in many months, the Prolimatech Megahalems has been out-performed. Cogage, the Thermalright spin-off company, offers excellent value in their TRUE Spirit cooler for only $39.95. The Cogage TRUE Spirit performance at an average of 36.0°C over ambient after five tests, and although the aftermarket bolt-through kit and Yate Loon fan come at an extra expense, the final product outperforms the bunch. Like clockwork, the Prolimatech Megahalems followed closely behind with an average temperature of 36.3°C over ambient, while the Thermalright Ultra-120 eXtreme trailed behind even further at 37.2°C over ambient. The giant-sized Scythe Mugen 2 SCMG-2000 performed at 38.6°C over, while the Xigmatek Thor's Hammer S126384 cooled down to 39.1°C over ambient. These five coolers are the Best CPU Coolers for overclocked LGA1366 processors as of Q3-2009.

Trailing less than six degrees behind the top leader and also paired with a Yate Loon high-output fan, the Corsair H50 CWCH50 offered standout performance with a total adjusted temperature of 41.5°C over ambient. Titan's FENRIR TTC-NK85TZ CPU cooler offered a impressive 42.5°C over, followed by the CoolAge FO-X120TF Wind Tunnel and Thermolab BARAM. If you're planning to overclock your computer beyond a reasonable threshold, then you'll want to make sure one of these coolers is on your parts list.

At 43.9°C over ambient the massive Tuniq Tower 120 Extreme offered respectable performance, but the $64.99 price tag is a little too far off from fair market value. The more affordable and equally effective Xigmatek HDT-S1283, OCZ Gladiator Max, or Kingwin XT-1264 each performed nearly as well, at half the size and cost. The OCZ Vendetta 2 OCZTVEND2, an old LGA775 favorite, performed at 45.7°C over ambient, while the Scythe Kabuto SCKBT-1000 trailed a full ten degrees behind the group leader and offered 46.0°C over.

All of these coolers will work extremely well in overclocked systems, and given the right circumstances some of the more tame coolers could perform just as well as the top products. Some of these coolers will accept a second fan, further improving results, while other are limited to only one. Taking cost into consideration, the field can been reduced to only a few real contenders. The ZEROtherm Nirvana NV120 Premium is an exception; the proprietary integrated fan cannot be exchanged for another high-output fan, such as the Yate Loon unit we've tested with. Because of this restriction, the NV120 PWM performed a marginal distance behind the others and wouldn't help an enthusiast achieve that top-speed overclock.

But wait, that's not all. In the next section, Benchmark Reviews compares our favored Yate Loon D12SH-12 against the Scythe Ultra Kaze 120x120x38mm fan, model DFS123812H-3000. Once you see the results, you'll reconsider using outrageously large 38mm thick cooling fans when excellent 25mm standard units exist.

Enthusiast Fan Comparison

Over the past few months there have been several requests by our readers for Benchmark Reviews to begin testing these coolers by using many different enthusiast level fans. While the idea seems interesting enough, the actual undertaking would be unreasonably time consuming. As it is now, each cooler already takes about two hours to install, prepare, and test; and most coolers receive five or more tests in stock and overclocked conditions. The test process for an individual cooler could take several days depending on ambient temperature and humidity.

In this section, we've taken the Yate Loon D12SH-12 that's been used for the past year of high-output testing and compared it to the Scythe Ultra Kaze, which is a 38mm thick enthusiast fan. I've heard a great number of enthusiasts claiming phenomenal results with the Ultra-Kaze, but it's not like me to believe hearsay. In this section, I've taken the opportunity to directly compare several 'high volume' test fans. Here's how it was done:

Lavalys EVEREST Ultimate Edition is used to create full loads on each core utilizing the system stability test (Stress CPU and Stress FPU options), and also measure individual CPU core temperatures. After a minimum of sixty minutes at full load, temperatures sustain a plateau and the ending ambient room temperature and individual CPU core levels are recorded. The fans are quickly replaced while the system is still under load, annd given thirty additional minutes with EVEREST loading the CPU cores before final temperature readings are again taken and recorded.

• Yate Loon 120x120x25mm model D12SH-12 (88 CFM @ 40 dBA) 12V/0.30A
• Scythe Kaze-Jyuni Slip-Stream 120x120x25mm fan, model SY1225SL12SH (110.31 CFM Advertised @ 37.0 dBA) 12V/0.53A
• CoolAge SX2 120x120x38mm fan, model CA-120SX2 (80 CFM Advertised @ 32 dBA) 12V/0.19A
• Scythe Ultra Kaze 120x120x38 model DFS123812H-3000 (133.6 CFM @ 45.9 dBA) 12V/0.60A

It becomes evident that there's a point of diminishing returns for every CPU cooler, and when 'over-fanned' the results collide closely together. Although the 2.67 GHz Intel Core i7-920 processor does a decent job of separating the crowd when these coolers wear their stock fan, once a high-output fan is attached there's really not much separating them all. So it's a good bet that most of these top-performing products could cool an overclocked system extremely well, but these days only the very best will do. Much like the Thermal Interface Material testing we've conducted, all of the high-performance products are beginning to perform at nearly the same levels. Eventually, I expect to see the same technology used in all cooling products with the difference being the application. This is where experience comes in handy, and we've shared some of this with you in our Best Thermal Paste Application Methods article. Remember, less is more when it comes to thermal paste, and soon CPU coolers may offer the same paradigm.

Taking a small collection of CPU coolers, Benchmark Reviews tested the performance of four different fans.

As you can see from the chart above, the Yate Loon 120x120x25mm model D12SH-12 fan performs the best compared to other enthusiast cooling solutions. Rated at 88 CFM by the manufacturer, I suspect that these are conservative figures. Operating on 0.30A, the Yate Loon D12SH-12 certainly moves a lot more air than suspected for a $7 fan. The real trick is in the operating voltage, which ranges from 6.5-13.8V, allowing enthusiasts to move the hot wire to either the 5V+ or 12V+ power lead. So until I'm given a good reason to think otherwise, Benchmark Reviews will continue to test high-output overclocked results with what I consider to be the best value in fans.

CPU Cooler Final Thoughts

It was around Q3-2008 when the final tests were conducted for the last LGA775 Socket-T Best CPU Cooler Performance article, and in many ways this Q3-2009 article could be repeating the same outcome. The recent launch of Intel's Core i5 series for the LGA1156 socket has really shaken the market. We tested the Intel Core i7-870 LGA1156 processor directly against the LGA1366 Core i7-920 in our P55 vs X58-Express platform comparison, and the P55 really dealt a lethal blow to overpriced 'enthusiast-designated' hardware. Perhaps a future Best CPU Cooler Performance article will feature coolers for the AMD AM3 platform, with their unlocked and ultra-affordable Black Edition Phenom-II processor series. Anything could happen, and we'd like to hear your feedback.

There is one minor drawback to using the Core i7 or Phenom II processors which affects overclockers: the difference in CPU cooler mounting dimensions. Many overclockers and enthusiasts have grown to cherish their favorite cooler, and trust them to cool the hottest system they can build. The problem is that now many manufacturers are offering free adapter kits, or include an adapter with their current model coolers, which leads to bigger problems because of processor differences. For all of our LGA1366 test products, we used the Xigmatek ACK-I7361 or ACK-I7363 CrossBow mounting kits whenever possible.

CPU coolers made for the LGA775 platform are designed for use with a Core 2 (Duo or Quad) or Pentium 4 and D processor with an integrated heat-spreader measuring 28.5 x 28.5mm (812.25mm total area), but the LGA1366 socket requires a much larger 32 x 35mm (1120mm total area) footprint to accommodate the extra 591 'pins'. Then there's the LGA1156 socket, which measure 30mm square for 900mm of area. If you use an LGA775 or LGA1156 cooler on a LGA1366 socket, your missing out on up to 38% (307.75mm) of the contact surface. Additionally, the cores are located in slightly difference locations; the Core 2 Quad is slightly spaced away from the center, while the Core i7 is concentrated there.

The Phenom II processor series from AMD offer a very large 37.31 x 37.31mm (1392.04mm total area) integrated heat-spreader surface, which is the largest processor surface I can recall since the original Intel Pentium (I) days. Compared to Intel's Core 2 Duo and Quad processors which measure 28.5 x 28.5mm, the Phenom II offers over 71% more contact surface area. If you compare the latest Intel Core i7 processors which measure 32 x 35mm, then the Phenom II series offers 24% more contact surface area. For overclockers, this will mean a much larger area to cool, but also much more manageable temperatures.

There are a lot of different products out there, and believe it or not we exclude a few from each article because they don't stack up well at all. So this is why you may not see some of the coolers other sites have tested in our results. Because of space and time limitations it's just simply not feasible to review them all, but it's certainly worth mentioning which products should be avoided. So I began to carefully think about it and nearly constructed a real-time chart which places products into different levels of performance. That's when I realized that performance is relative, too, and what performs well today might be considered low-end only a year from now. Perhaps the best method for testing is to use a synthetic system to generate the same exact load for each and every test conducted. This would stand the test of time much better than any computer system or processor platform would, because temperature is a static measurement, but it wouldn't take into account the differences seen between processor model architecture.

The synthetic test unit might generate 250W of thermal energy, but every CPU series has a different layout and might not mate perfectly to a particular cooler. This brings me to my final point: there's a cooler for every processor and purpose. The ordinary casual computer user is fine with the included thermal cooling solution that comes with the retail processor kit. Systems built with a Core 2 Duo processor and three-piped HDT cooler (like the HDT-S1283 or Vendetta 2) will not be cooled the same as a Core 2 Quad processor because of where the cores align with the heat-pipes. Likewise, coolers built around the Core 2 LGA775 design may not perform well at all with the Core i7 or Phenom II platforms. This is why the research is so critical, and understanding the product is important.

Best CPU Cooler Conclusion

When I first examined the Cogage TRUE Spirit, I could see that it was a slightly scaled-down version of the Thermalright Ultra-120 eXtreme. I didn't think much of it, and actually figured that it would trail the larger TRUE in cooling performance. Perhaps that's the beauty of these article, because it's truly anybody's game. There's no denying that the Prolimatech Megahalems offered near-identical performance, and that's fine if choose to ignore price. For the rest of the cost-conscious world however, the choice is clear. Even if you add an aftermarket Thermalright LGA1366 Bolt-Thru-Kit onto the $40 product cost, the Cogage TRUE Spirit still offers a better value than the others.

Consider that the Megahalems costs $65, the Thermalright Ultra-120 eXtreme (TRUE) costs $60, and the Xigmatek Thor's Hammer S126384 sells for $65, yet all three of these top-performers still require you to purchase a cooling fan. Once you factor shipping and at least one $7 fan you'll still be paying almost twice what you would for the Cogage TRUE Spirit. It seems that the aftermarket CPU cooling industry is about to have its first price correction, and it couldn't happen at a better time.

It's been very quiet around the CPU cooling industry these past three months, as evidenced by the lack of high-end products launched to market. The opposite is true for overclockers, since the longtime popular Intel Core 2 and Core i7 brands are now competing with the AMD Phenom II series. Previously an overclock was limited by the CPU, but AMDs decision to offer unlocked Black Edition (BE) processors at mainstream prices have removed this roadblock. Still, AMDs socket AM3 platform will need to work overtime in order to beat the new line of LGA1156 socket Core i5/i7 processors.

For enthusiasts and overclockers, there's still plenty of life left in the older socket platforms and the retail pricing proves it. The quad-core Q8200 and Core 2 Duo E8400 each sell for around $165, unchanged for almost a year now and proving that demand for the LGA775 platform still exists. LGA775 products still provide decent value and give hardware enthusiasts a reason to continue using P45 and X48 chipsets, but they don't compare to the performance of Intel's Core i7 series or even touch the value of an AMD Phenom II processor.

Dual-core processors are still strong for gamers and multitaskers, while quad-core processors work best for audio/video editing and virtual computer servers. AMD's Phenom II launch has done wonders for the enthusiast and overclocking community, with efforts further amplified by offering affordable high-end products during an economic recession. For the money, there isn't a processor around that comes close in value or performance than the AMD Phenom II X3 720 Black Edition unlocked triple-core socket AM3 processor that sells for only $119 (and earned it the Benchmark Reviews Editor's Choice Award). If quad-core is more to your liking, the AMD Phenom II X4 955 BE removes the clock multiplier restriction at a mainstream price around $189; something Intel's Extreme Edition processor offers for more than $1000.

While not every CPU cooler tested in this article is suitable for extreme overclocking projects, practically all of these products offer excellent cooling performance for high-end systems. Benchmark Reviews offers a beginners how-to guide for enthusiasts wanting to overclocking their CPU, so join in and see how far you can stretch that dollar! I've already delivered my choices for the LGA775 platform way back in the Best of Q4 2008 Conclusion, and not much has changed. The newer Intel Core i7 platform is still maturing despite the introduction of LGA1156/Core i5, so so more great products are still expected to compete in the market space.

LGA1366 Recommendations

Obviously there's a world above and beyond the 3.8GHz @ 1.4V overclock we put on our Core i7-920, and if Intel would like to help sponsor our series we could use an Extreme Edition CPU to find out exactly where the limit is. Presuming that overclockers aren't going to limit themselves to the i7-920 for their X58 projects, I see several opportunities for high-performance cooling. Here are my suggestions for extreme LGA1366 cooling projects:

For absolute performance my recommendation goes to the Prolimatech Megahalems. This product is designed by former Thermalright engineers, and takes the best aspects into consideration to produce one phenomenal product. The mounting base is unparalleled by any other I've ever tested, and delivers extraordinary contact surface pressure between the processor and polished finish on the Megahalems. As of October 2009 the ProlimaTech Megahalems was available at FrozenCPU for $65. Make sure to add two Yate Loon D12SH-12 fans in a push-pull configuration for $7 each, and you'll find that only chilled liquid cooling can outperform it.

Another option is the Thermalright Ultra-120 eXtreme (TRUE) for $60, or the TRUE Black Ultra-120 eXtreme for $75. Add the same two Yate Loon D12SH-12 fans in a push-pull configuration for $7 each along with the $6 Thermalright Fan Bracket, and you'll be ready for some high-temperature overclocking.

Since the Scythe Mugen 2 SCMG-2000 kit is available at NewEgg for $34.99, and it comes with a strong bolt-through mounting kit and Scythe Slip-Stream fan, there's really very little additional cost to consider. The Mugen-II worked great in stock form, but overclockers will definitely want to upgrade the fan and possibly use a push/pull combination to drive air through the massive heatsink. Of all the 'large' heatsinks tests, the SCMG-2000 kit offers the best value.

The Xigmatek Thor's Hammer S126384 is available from NewEgg for $65, which includes the CrossBow ACK-I7363 mounting system with the CAC-SXHH7-U01 kit and allows two 120mm fans of either 25mm or 35mm depths. Thor's Hammer can handle two 120mm fans, and my pick would be the Yate Loon D12SH-12 fans in a push-pull configuration for $7 each.

Obviously the Thermalright Cogage TRUE Spirit is an excellent choice, but four heat-pipe rods limit the thermal range this cooler can handle compared to more robust coolers. You'll want a better fan (or two), and the aftermarket Thermalright LGA1366 Bolt-Thru Kit for an extra $10, but there's certainly some performance to be had from the TRUE Spirit.

Beyond these five top-performers, there's only a handful of other CPU coolers I might consider worthy of high-temperature overclocking projects on the LGA1366 socket. The Titan FINRIR TTC-NK85TZ and Thermolab BARAM are two good products, but North American availability is scarce if not impossible. More likely to stocked is the Cooler Master Hyper Z600 RR-600-NNU1-GP kit for $58 or Xigmatek HDT-S1284EE which sells for $38 at NewEgg. Each of these kits offers LGA1366 compatibility, and each comes with a capable cooling fan (although the Hyper Z600 can fit four 120mm units).

Some of the older products still deliver great performance, even against the newest top-performers. The classic Xigmatek HDT-S1283 is a product that has spawned at least a dozen clones. The grandfather of HDT still performs among the best products we test, presently sells for $40. An even better price on the exact same design can be found in the Kingwin RVT-12025, an exact clone of the HDT-S1283, but with a silent fan. The RVT-12025 presently sells for only $22, making it the most affordable top-performance product available; leaving money to upgrade the fan and mounting kit. There really are a lot of options out there, and hopefully this series has helped clarify your decision.

This concludes the Best CPU Cooler Performance LGA1366 - Q3 2009 roundup article. If you have constructive suggestions, Benchmark Reviews encourages you to leave comments and questions in our Discussion Forum.

EDITOR'S NOTE: Benchmark Reviews will publish our Q1-2010 Best CPU Cooler Performance LGA1366 article on 11 March 2010. Several new heatsinks along with some enthusiast favorites will all be tested on an overclocked six-core Intel processor. Additionally, our performance test results for the AMD AM3 socket will also be included.

EDITOR'S NOTE: The Scythe Mugen-2 Revision B model SCMG-2100 heatsink is identical to the first version, model SCMG-2000. The only difference is that Mugen-2 Rev. B uses a newly developed F.M.S.B. (Flip Mount Super Back-Plate) for more convenient mounting onto the motherboard. There should not be any cooling performance between these two models, despite marketing hype.

Epilogue - Looking Forward

What comes next? The Intel P55-Express chipset has opened up mainstream hardware to various tweaking projects, but it doesn't hit the target for hardcore enthusiast overclockers. Chances are very good that the Best CPU Cooler Performance Q4-2009 article will feature more high-end LGA1366 cooling products; at least until a processor with higher TDP is made popular among overclockers.

Sometimes a well-planned project still suffers problems, and even though Benchmark Reviews works closely with manufacturers and distributors we still miss the opportunity to test new products from time to time. In our next article, we plan to include the following CPU coolers:

• Dynatron G950 Genius
• Xigmatek Balder SD1283
• Xigmatek Odin's Wing

Although we made several requests for product samples, there were a few companies who declined to have their product compared against others in our Best CPU Cooler Performance series.

• Evercool Buffalo HPFI7-10025 CPU Cooler
• Rosewill FORT120 RCX-SHDT120X1 CPU Cooler

Related Articles:

• Vendetta 2 vs TRUE vs HDT-S1283
• Intel DX58SO Smackover X58 Motherboard
• Best CPU Cooler Performance: Intel Q3-2010
• Best CPU Cooler Performance - Q3 2008
• Best CPU Cooler Performance LGA1366 - Q1 2009
• Best CPU Cooler Performance Q2-2010
• ProlimaTech Super Mega Heatsink CPU Cooler
• Best CPU Cooler Performance Intel/AMD Q1-2010
• Intel Core i7-965 Extreme Edition Processor
• Gigabyte GA-EX58-UD4P X58 Motherboard