AMD Athlon-II X2-255 AM3 Processor Review

In late January 2010, AMD released a new series of processors that fills in some of the gaps in their Athlon-II and Phenom-II Dual, Triple, and Quad-Core Lines. Most of the newly released processors are really just 100Mhz clock speed bumps on the old versions. Today at Benchmark Reviews we are focusing on the newly released ADX255OCGQBOX AMD Athlon-II X2-255 AM3 processor. Based on the Regor core, the Athlon-II X2-255 has a 3.1Ghz clock speed, up 100Mhz from the Athlon-II X2-250 at 3.0GHz which was released last summer. The Athlon-II X2-255 is at the very low end of the newly released processors and represents a very value based market at only $74.99 over at NewEgg.com. Benchmark Reviews is going to use the Athlon-II X2-255, with its support for DDR2 RAM up to 1066Mhz as well as DDR3 RAM up to 1333Mhz, to show some of the great upgrade options available for consumers who have been waiting for a low-cost option to a better computer system.

AMD is quickly moving into the leader position in the low to mid-range computing world. Their firm grasp on the sub $200 market is expanding rapidly. The lower end of their processor line, the Athlon-II line, has expanded from just X2 (dual core) CPUs last year to the X3 (triple core) and X4 (quad core) processors like the Athlon-II X4-620 which brings quad core processing to under $100. AMD is also breaching the high end of gaming PCs with their Phenom-II line. The black edition series of processors, including the Phenom-II X4-965BE which won an editor's choice award here at Benchmark Reviews, can be overclocked to extreme highs, making them great gaming CPUs. They can't beat the raw power of the i7 series, but with the 965BE coming in at only $179, the bang for the buck is appealing to computer enthusiasts everywhere.

The Athlon-II series is built to be a less expensive alternative, while still offering a lot of great features. The chips are designed without any L3 cache at all, allowing for those lower prices. Many computer enthusiasts, myself included, often wait a long time after the purchase of a computer before considering an upgrade. I know many of you reading this are the same way. According to the Steam Hardware Survey for January 2010, almost 21% of gamers (remember, the hardware survey is based on Steam users) are still using single core processors in their systems. And that's coming off one of the most sale studded holiday seasons ever. Quad core use is up, but still only amounts to 20% of users. That means that there are more gamers out there with single core processors than quad cores. The bulk of the users use dual core processors with speeds between 2.0 and 2.6GHz. This leaves a lot of room for upgrade.

In this article, Benchmark Reviews will be upgrading from two Intel dual core systems currently used as media PCs and for playing popular games, and converting over to an AMD system using the Athlon-II X2-255 AM3 Processor. This will give us a good idea of the differences in performance and it will allow us to see if the lower-than-ever-prices being offered by AMD for its processors can justify the upgrade. After all, we would all love to have a powerhouse computer, but it comes down to what we can afford to spend on our computer gaming vice. We will also overclock the AMD Athlon-II X2-255 to see just how much power we can get out of it. Join us now as we take apart AMD's latest entry in their lower end Athlon-II line.

About Advanced Micro Devices, Inc (AMD)

"Advanced Micro Devices (NYSE: AMD) is an innovative technology company dedicated to collaborating with customers and partners to ignite the next generation of computing and graphics solutions at work, home, and play.

Over the course of AMD's three decades in business, silicon and software have become the steel and plastic of the worldwide digital economy. Technology companies have become global pacesetters, making technical advances at a prodigious rate - always driving the industry to deliver more and more, faster and faster.

However, "technology for technology's sake" is not the way we do business at AMD. Our history is marked by a commitment to innovation that's truly useful for customers - putting the real needs of people ahead of technical one-upmanship. AMD founder Jerry Sanders has always maintained that "customers should come first, at every stage of a company's activities."

We believe our company history bears that out."

Athlon-II X2 AM3 Features

AMD Direct Connect Architecture

An award-winning technology designed to reduce bottlenecks that can exist when multiple components compete for access to the processor bus. Competing x86 systems use a single front-side bus (FSB) which must carry memory access, graphics, and I/O traffic. Eliminate the FSB, and you can reduce delays that competing access requests can cause.

45 nm Process Technology with Immersion Lithography

More efficient process technology with cutting-edge lithographic performance puts more transistors in less space.

AMD Wide Floating Point Accelerator

Doubles processor bandwidth from 64- to a full 128-Bit Floating-Point math processing pipeline that can double many of the bandwidth paths that help keep it full.

AMD Digital Media XPress 2.0 Technology

Provides support for SSE, SSE2, SSE3, SSE4a, and MMX instructions for digital media applications and security.

CPU Architectural Features

True Multi-Core Processing

The extensive AMD64 architectural optimizations and features enable thorough integration of multiple cores within the same processor, with each core having its own L1 and L2 caches.

AMD Dedicated Multi-Cache

Each core has its own dedicated L2 cache, which enables simultaneous independent core access to L2 cache, eliminating the need for cores to arbitrate for cache access. This helps reduce latency on L2 cache accesses.

AMD Virtualization (AMD-V) Technology

Silicon feature-set enhancements designed to improve the performance, reliability, and security of both existing and future virtualization environments.

AMD PowerNow! 3.0 Technology

The latest power management technologies that deliver performance on demand when you need it, and power savings when you don't.

HyperTransport 3.0 Technology

Third-generation HyperTransportTM interface improves performance, supporting transfer speeds up to 4.4GT/s.

Simultaneous 32-bit and 64-bit Computing

AMD64 technology enables a breakthrough approach to 64-bit computing that doubles the number of registers in the processor and allows PC users to use today's 32-bit software applications while enabling them to also use the next generation of 64-bit applications.

Cool'n'Quiet 3.0 Technology

Up to eight different performance states help enhance power efficiency. Simplified performance state transitions can reduce latency and the software overhead of performance state changes.

AMD Dynamic Power Management

Each processor core, and the integrated memory controller and HyperTransportTM controller, is powered by dedicated voltage planes.

Integrated Dual-Channel Memory Controller

Directly connects the processor to memory for optimum performance, low latency, and high throughput.

Multi-Point Thermal Control

The next-generation design features multiple on-die thermal sensors with digital interface. Automatic reduction of p-state when temperature exceeds pre-defined limit. Additional memory thermal management interface.

AMD CoolCore Technology

Coarse and fine transistor control that can automatically reduce processor energy consumption by turning off unused parts of the processor.

ADX255OGQBOX Specifications

• Model Number & Core Frequency: X2 255 = 3.1GHz
• TRAY OPN# ADX255OCK23GQ
• PIB OPN# ADX255OGQBOX
• L1 Cache Sizes: 64K of L1 instruction and 64K of L1 data cache per core (256KB total L1 per processor)
• L2 Cache Sizes: 1MB of L2 data cache per core (2MB total L2 per processor)
• Memory Controller Type: Integrated 128-bit wide memory controller *
• Memory Controller Speed: 2.0GHz with Dual Dynamic Power Management
• Types of Memory Supported: Support for unregistered DIMMs up to DDR2-1066MHz -AND- DDR3-1333MHz
• HyperTransport 3.0 Specification: One 16-bit/16-bit link @ up to 4.0GHz full duplex (2.0GHz x2)
• Total Processor-to-System Bandwidth: Up to 33.1GB/s bandwidth [Up to 17.1 GB/s total bandwidth (DDR3-1066) + 16.0GB/s (HT3)]
• Up to 28.8GB/s bandwidth [Up to 12.8 GB/s total bandwidth (DDR2-800) + 16.0GB/s (HT3)]
• Packaging: Socket AM3 938-pin organic micro pin grid array (micro-PGA)
• Fab location: GLOBALFOUNDRIES Fab 1 Module 1
• Process Technology: 45-nanometer DSL SOI (silicon-on-insulator) technology
• Approximate Die Size: 117.5 mm2
• Approximate Transistor count: ~ 234 million
• Max Temp: 74 Celsius
• Core Voltage: 0.85-1.425V
• Max TDP: 65 Watts
• MSRP: $74.99

*Note: configurable for dual 64-bit channels for simultaneous read/writes

Closer Look: Athlon-II X2-255

The Athlon-II X2-255 is based on the Regor die. Regor is a native dual core die that is 117.5 mm2 and it has a transistor count of around 234 million transistors. The die is quite a bit smaller than the Phenom-II die, Deneb. This smaller size is primarily due to the lack of L3 cache altogether. The die is built using a 45 nm process technology with AMD's Immersion Lithography, which they say allows them to put more transistors in a smaller area. The Athlon-II X2-255 also has a 65 Watt TDP (Thermal Design Power/Point). The TDP is the max amount of power dissipated by the processor under normal circumstances. It isn't the max amount of power that the processor can consume, as overclocking and other circumstances might cause the CPU to draw more power that its TDP. The 65 Watt TDP for the Athlon-II X2-255 is the same for almost all the Athlon-II X2 processors, but it is quite a bit lower than X3, X4 or Phenom lines. This means you should have less heat and power consumption to worry about under normal operating settings.

I want to mention quickly that the AMD website shows the Athlon-II X2-255 as having just 512K of L2 cache per core, for a total of 1MB. This is not correct, as is shown below by CPU-Z. Other places on the AMD website show the correct amount to be 1MB per core for a total of 2MB of L2 cache. The 2MB is in line with the other Athlon-II X2 processors, and reflects that there has not been a change in L2 cache size from the Athlon-II X2-250.

There are some differences between the Athlon-II X2-250 and its new counterpart, the Athlon-II X2-255. The first, and most obvious, is the 100Mhz bump in speed. As noted in CPUZ, the clock speed of the Athlon-II X2-255 is 3.1GHz. Another difference here is the RAM support. The X2-250 processor supported DDR2 RAM up to 800Mhz and DDR3 RAM up to 1066Mhz. The Athlon-II X2-255 bumps that up as well, increasing the compatibility with DDR2 to 1066Mhz and DDR3 to 1333Mhz. The Athlon-II X2-255 is being called Revision DA-C2.

Other than that, the X2-255 is pretty identical to the X2-250, keeping the same 200Mhz bus speed and 2000Mhz HT Link. The HT Link was bumped up by 200Mhz for the Althon-II X2 line from the Athlon X2 line. The Athlon-II X2-255 is a Socket AM3 processor, but it can be used in a Socket AM2+ motherboard as well.

The memory controller for the Athlon-II X2-255 matches the HT Link at 2000Mhz and can be configured as either one 128 bit channel or two 64 bit channels. As I mentioned before, the supported memory is listed as DDR3-1333, but just as its predecessor, the X2-250, I'm sure it will easily support the DDR3-1600 memory in our test system. Also like its predecessor, the Athlon-II X2-255 comes with full virtualization support through AMD-V technology. This will be important if you plan on using XP mode in Windows 7.

I have been a little confused since recieving the Athlon-II X2-255 processor by its exact differences with the X2-250 processor. After my research, it appears that the two chips are almost exactly the same. The core multiplier on the X2-255 is set at 15.5 rather 15 and since the X2-255 is not a black edition processor, the multiplier is locked. That is not to say that the two processors are equal in their capabilities, however. With the higher multiplier, the Athlon-II X2-255 may have better overclocking capabilities. Also, as is normal in the technology industry, having made these processors for quite a while now, AMD will have become more efficient in producing better yields. The current processors will be more stable than their predecessors, especially when pushing them to the limit. Simply by increasing the bus speed to 250Mhz, I was able to achieve a stable overclock of the Athlon-II X2-255 to 3.8GHz. The most stable overclock I found was with the multiplier set down to x15 and the bus speed increased to 255 as seen above. With a little more tweaking, you could probably get this processor up to 4.0GHz cooled by air alone.

Testing and Results

Before I begin any benchmarking or overclocking, I thoroughly stress the CPU and memory by running Prime95 on all available cores for 12 hours. If no errors are found, I move on to a gaming stress test. To do this, I use Prime95 again to stress the processor, while running an instance of FurMark's stability test on top of this. If the computer survives this test for 2 hours without lockup or corruption, I consider it to be stable and ready for overclocking. After achieving what I feel is stable overclock, I run to these tests again for certainty. The goal of this stress testing is to ensure the clock speeds and settings are stable before performing any benchmarks. I adopted this method from another writer here at Benchmark Reviews and it seems to do a great job of flushing out what only seem to be stable overclocks.

Once the hardware is prepared, we begin our testing. Each benchmark test program begins after a system restart, and the very first result for every test will be ignored since it often only caches the test. This process proves extremely important in the many gaming benchmarks, as the first run serves to cache maps allowing subsequent tests to perform much better than the first. Each test is completed five times, with the average results displayed in our article.

For our Athlon-II X2-255 review, the following test systems and comparison processors will be used. As was mentioned before, the Athlon-II X2-255 will be compared to older systems to judge its value as an upgrade option. We fully anticipate the the Athlon-II X2-255 to be the fastest processor in our test-bed for this review. If it is not, we would be disappointed in the performance it provides for its price. At $67, the Pentium Dual Core E5300 2.6GHz is very close in price to the Athlon-II X2-255, at $75 and 3.1GHz. We expect to see a better than $8 increase in performance between the two processors. The Core 2 Duo E6300 is an old Conroe processor running at 1.8GHz. We hope to see that the Athlon-II X2-255 provides a large performance increase, and thus an inexpensive upgrade opportunity, over the Core 2 Duo E6300.

Intel LGA775 Test System 1

• Processors: Intel Core 2 Duo E6300 1.8GHz
• Motherboard: MSI P965 NEO LGA775
• System Memory: 2x2GB Corsair DDR2 (800MHz@5-5-5-18)
• Video: MSI NVIDIA GeFORCE 9800GTX+
• Disk Drive: SEAGATE Barracuda 1.5TB SATA
• Optical Drive: ASUS DRW-24B1ST DVD Burner
• PSU: 650W
• Enclosure: NZXT GAMMA
• Operating System: Windows 7 Home Premium x64

Intel LGA775 Test System 2

• Processors: Intel Pentium Dual Core E5300 2.6GHz
• Motherboard: Intel BOXDG41MJ LGA775
• System Memory: 2x2GB Corsair DDR2 (800MHz@5-5-5-18)
• Video: Intel GMA4500 On-Board
• Disk Drive: Western Digital Caviar 320GB SATA
• Optical Drive: Panasonic 8X DVD-RW
• PSU: 650W
• Enclosure: NZXT GAMMA
• Operating System: Windows 7 Home Premium x64

AMD Socket AM3 Test System

• Processors: AMD Athlon-II X2-255
• Motherboard: ASUS M4A785TD-M EVO
• System Memory:2x2GB Patriot Gamer Series DDR3 (1600MHz@9-9-9-24)
• Video: ATI Radeon HD4200 On-Board with 128Mb Side-Port Memory (DDR3 1333Mhz@6-6-6)
• Disk Drive: Western Digital 400Gb SATA
• Optical Drive:ASUS DRW-24B1ST DVD Burner
• PSU: 650W
• Enclosure:NZXT GAMMA
• Operating System: Windows 7 Professional x64

Benchmark Applications

• EVEREST Ultimate Edition v5.00.1650 by Lavalys
• Passmark PerformanceTest v6.1
• PCMark Vantage v1.0.2.0 by Futurmark Corporation
• Resident Evil 5 Benchmark
• Street Fighter 5 Benchmark

EVEREST Benchmark Tests

Lavalys EVEREST is an industry leading system diagnostics and benchmarking solution for enthusiasts PC users, based on the award-winning EVEREST Technology. During system optimizations and tweaking it provides essential system and overclock information, advanced hardware monitoring and diagnostics capabilities to check the effects of the applied settings. CPU, FPU and memory benchmarks are available to measure the actual system performance and compare it to previous states or other systems. Furthermore, complete software, operating system and security information makes EVEREST a comprehensive system diagnostics tool that offers a total of 100 pages of information about your PC.

The Athlon-II X2-255 starts off the testing by meeting our expectations of increased performance over the two Intel CPUs. It appears that without the additional overhead of an L3 cache, memory bandwidth is slightly ahead of the pack. Read bandwidth is increased by 55% over the Dual Core E5300 and write speed is increased by 47%. The most notable increase in bandwidth speeds comes from copy tests, which are increased by an amazing 136%. Remember, also, that the Athlon-II X2-255 is running with DDR3 memory where they other two test systems are using DDR2.

In the CPU integer performance tests, the trend is continued by showing the better performance offered by the Althon-II X2-255. The PhotoWorxx test shows a 41% performance boost and the Queen tests shows an increase of 39%.

Once again, the floating point tests show the same trend. Performance using the Athlon-II X2-255 is enhanced throughout all of the tests at 51% in the Sin Julia test, 39% in the Mandel test, and 12% in the Julia tests. The results of the Everest tests all show us right off the bat that the ADX255OCK23GQ provides a very viable option for users looking to upgrade older computer systems. Even at a price of only $8 more than the Intel Dual Core E5300, it outperforms the slower processor by quite a bit. Let's move on and see if further testing continues to show this trend.

Passmark Performance Test

PassMark PerformanceTest is a PC hardware benchmark utility that allows a user to quickly assess the performance of their computer and compare it to a number of standard 'baseline' computer systems. The Passmark PerformanceTest CPU tests all benchmark the mathematical operations, compression, encryption, SSE, and 3DNow! instructions of modern processors.

In our tests there were several areas of concentration for each benchmark, which are combined into one compound score. This score is referred to as the CPU Mark, and is a composite of the following tests: Integer Math, Floating Point Math, Find Prime Numbers, SSE/3DNow!, Compression, Encryption, Image Rotation, and String Sorting. For this review, we've also decided to run the memory benchmark, which results in a composite score based on the following tests: small block allocation, cached read, uncached read, write performance, and large block allocation.

The Passmark performance tests show a much different result than the Everest tests. The stock Athlon-II X2-255 was outperformed by the Dual-Core E5300 running at just 2.6GHz. When overclocked to 3.8GHz, the X2-255 ADX255OCK23GQ was able to eke out a slight performance gain over the stock Intel Dual-Core. The performance increase over the 1.8GHz Core 2 Duo was very evident in both the stock and overclocked states of the Athlon-II X2-255.

In the memory marks, the AMD X2-255 did register very slight gains over the Dual Core E5300, but only by a little, even running DDR3 memory over the DDR2 on the Intel platform. I have realized through many other testing setups that the Passmark memory marks generally have very little difference based on memory clock speed, but I think we should have seen a bigger difference between the DDR2 and DDR3 memory.

PCMark Vantage Benchmark Tests

PCMark is a series of computer benchmark tools developed by Futuremark. The tools are designed to test the performance of the user's CPU, read/write speeds of RAM and hard drives. We have used these tests to simulate a battery of applications and tasks, which will produce results we can compare to other systems using similar hardware.

The PCMark Vantage test results give us renewed hope in the performance of the AMD Athlon-II X2-255 CPU, especially in gaming performance. The Athlon-II delivers superior performance in every aspect of the testing. The TV and Movies suite tests media transcoding and HD playback. Surprisingly enough, the Intel GMA4500 GPU on the Dual Core E5300 platform outperforms the GeForce 9800GTX+ on the Core 2 Duo platform. The Radeon HD 4200 paired with the Athlon-II X2-255 easily outperforms both of the other systems.

The gaming suite shows even the much slower 1.8GHz Core 2 Duo platform outperforming the Dual Core 2.6GHz system. This is likely due to the 9800GTX+ video card used in the Core 2 Duo system. Even with the added GPU power, the stock Athlon-II X2-255 nearly doubles the score of the Core 2 Duo platform. When overclocked, the gaming results for the Athlon-II X2-255 skyrocket, nearly doubling the stock scores and improving performance over the Core 2 Duo platform by 264%. I was so surprised by these results after the first testing that I ran the tests over again on each of the systems. The results did not significantly change. These results are unlikely to reflect actual real-world performance increases, as we will see later in our gaming benchmarks.

The PCMark music suite tests not only audio transcoding, but also webpage rendering using popular web-based music store formats. The Athlon-II X2-255 once again easily outpaces the performance of the two Intel platforms and more than doubles the score of the Dual Core platform when overclocked to 3.8GHz.

SiSoftware Sandra

SiSoftware Sandra (the System ANalyser, Diagnostic and Reporting Assistant) is an information & diagnostic utility. It should provide most of the information (including undocumented) you need to know about your hardware, software and other devices whether hardware or software.

It works along the lines of other Windows utilities, however it tries to go beyond them and show you more of what's really going on. Giving the user the ability to draw comparisons at both a high and low-level. You can get information about the CPU, chipset, video adapter, ports, printers, sound card, memory, network, Windows internals, AGP, PCI, PCI-X, PCIe (PCI Express), database, USB, USB2, 1394/Firewire, etc.

The SANDRA DhryStone and Whetstone tests are CPU tests that run completely within the CPU + cache memory itself. These tests are perfect for seeing general efficiency per processing core. Dhrystone is basically a suite of arithmetic and string manipulating programs and is an older CPU tests. Even so, it remains a simple and accurate way to show RAW CPU processing performance. The whetstone benchmark primarily measures floating-point arithmetic performance.

As expected, the Athlon-II X2-255 leads the pack in the Sandra Arithmetic Test suite. The Athlon-II X2-255 stays ahead of the Dual Core E5300 by 14% in the dhrystone tests and by 9% in the whetstone tests. The results are more impressive when the X2-255 is overclocked. The Sandra CPU Test suite further exemplifies they ability of the Athlon-II X2-255 to offer superior upgradeability for a budget minded user.

Video Game Benchmarks

PC-based video games can depend heavily on the CPU if the attached GPU (Graphics Processing Unit) is less powerful, or the graphics settings are configured so low that they create no strain on the video card and rely purely system processing speed; a phenomenon known as CPU-dependence. The opposite is true when the video game has a powerful video card installed, and can handle all graphical demands without receiving assistance from the CPU. Since it is unlikely that someone spending enough money to buy a top-of-the-line graphics card would settle for the Athlon-II X2-255 as their gaming processor, we have decided to use the on-board video solutions provided with many entry level motherboards for these gaming tests. The Street Fighter 5 gaming benchmark is among the newest additions to Benchmark Reviews' testing suite. As multi-threaded gaming tests, these will stress our components sufficiently enough that we should be able to see just how well the Athlon-II X2-255 performs in a modern gaming environment.

For the Gaming Benchmarks we have limited our test bench to just the Athlon-II X2-255 and the Intel Dual Core E5300 platforms. The Core 2 Duo platform uses a 9800GTX+ video card which is likely to skew the results dramatically. The Athlon-II X2-255 is paired with a Radeon HD 4200 on-board GPU, which should be much more comparable to the GMA4500 GPU used by the Dual Core system. Neither of these GPUs represent gaming hardware, as the results will show.

Built upon an advanced version of Capcom's proprietary MT Framework game engine to deliver DirectX 10 graphic detail, Resident Evil 5 offers gamers non-stop action similar to Devil May Cry 4, Lost Planet, and Dead Rising. The MT Framework is an exclusive seventh generation game engine built to be used with games developed for the PlayStation 3 and Xbox 360, and PC ports. MT stands for "Multi-Thread", "Meta Tools" and "Multi-Target". Games using the MT Framework are originally developed on the PC and then ported to the other two console platforms.

On the PC version of Resident Evil 5, both DirectX 9 and DirectX 10 modes are available for Microsoft Windows XP and Vista Operating Systems. Microsoft Windows 7 will play Resident Evil with backwards compatible Direct3D APIs. Resident Evil 5 is branded with the NVIDIA The Way It's Meant to be Played (TWIMTBP) logo, and receives NVIDIA GeForce 3D Vision functionality enhancements. NVIDIA and Capcom offer the Resident Evil 5 benchmark demo for free download from their website, and Benchmark Reviews encourages visitors to compare their own results to ours.

Regardless of processing power, with the on-board graphics, neither of these CPUs can give us playable frame rates in Resident Evil 5. The tests were completed with the lowest settings possible at the most likely gaming resolution of 1280x1024. In order to play the game, you will need to invest in a discrete GPU.

The results from the Street Fighter 5 benchmark are consistent with the Resident Evil 5 benchmark scores. Neither the Athlon-II X2-255 nor the Dual Core E5300 can muster enough frame rates to play the game without trouble. We are not surprised by the results of the gaming tests. In both cases, the Athlon-II X2-255 platform slightly outperforms the Intel Dual Core platform. This may have a lot to do with the performance of the Radeon HD 4200 over the GMA4500 as well. In any event, paired with a better video card, it is highly likely that the Athlon-II X2-255 would be a viable solution for playing either of these two modern games. You will just have to spend a bit more to get there.

AMD Athlon-II X2 Final Thoughts

The launch of the Athlon II brand marks a complete 45nm refresh of AMD's mainstream and enthusiast processors. On the high end, we have the Phenom-II X4's and X3's that launched a few months ago. Below that will be the recently launched Phenom-II X2 series, although some of these may actually be faster than the low end X3's in single-threaded applications. That leaves the Athlon-II X2's one notch lower, sitting directly in the mainstream market segment. The performance we've seen throughout our testing shows the Athlon-II X2-255 outperforming a similarly (although lower) priced Intel Dual Core CPU. It also represents an excellent upgrade opportunity from an older Conroe based Core 2 Duo CPU. The Athlon-II X2-255, along with other low priced AMD processors in the Athlon-II and Phenom-II line should be taken into consideration when evaluating your options for upgrading a machine that is getting to be out of date, especially when a new motherboard is a necessity as well.

We represented the Conroe based Core 2 Duo in this article to show this exact scenario. While the NEO P965 motherboard is an LGA775 board, it will not support newer Wolfdale Intel LGA775 processors. This severely limits the upgradeability of this motherboard, causing most users to need a new motherboard altogether. While the newer LGA775 motherboard used in the Dual Core platform will accept newer Intel LGA775 processors, we have shown that the Athlon-II X2-255 outperforms similary priced LGA775 CPUs. It is likely that this result will carry forward with other Athlon-II and Phenom-II processors.

Continuing on with AMD's Ahtlon-II line, X3 and X4 processors have been released. In fact, AMD now offers a quad-core processor for under $100. The Athlon-II line is certainly set to provide budget minded users with a whole new array of possibilities. Without the cache, the Athlon-II's will be a bit slower than their Intel counterparts in some applications, but will also be less expensive and consume less power.

ADX255OGQBOX Conclusion

The Athlon-II X2-255 performed very well against our Intel processors. The goal of this article was to find out how viable the Athlon-II X2-255 is as an upgrade option for budget minded users who want to get more out of their computers. Many users may not have uprgaded in quite a while. The Athlon-II X2-255's performance shows that it can beat a similarly priced Pentium Dual Core processor nearly across the board. The X2-255 also provides an impressive boost for users running older systems such as the Conroe based Core 2 Duo used in this review. Without a decent graphics card, the Athlon-II X2-255 is unable to play the latest games, but this shouldn't be an issue for most users looking to upgrade to the X2-255.

The Athlon-II X2-255 passed our stress test and completed all benchmarks without a hint of instability. Even overclocked to 3.8GHz, the X2-255 never faltered. It seems that the only difference between the X2-255 and the X2-250 is the higher stock CPU multiplier. This alludes to the fact that the AMD Athlon-II chips have seen improving yields over the course of their production. The latest additions to the Athlon-II line, including the Athlon-II X2-255 will be at least as stable as their forerunners and likely more so. Any one wanting to try their hand in the overclocking market that needs to operate on a budget would have a lot of fun with the Athlon-II X2-255.

AMD has made it possible for their Athlon-II line to run in AM2+ motherboards as well as AM3 motherboards. This allows the door to be wide open for the choice of motherboard with which the Athlon-II X2-255 will function. The motherboard we used to test the Athlon-II X2-255 is the ASUS M4A785TD-M EVO AM3 motherboard using the 785G Chipset. The Athlon-II X2-255 functions extraodinarily well with this motherboard. I would expect that the X2-255 be used with a lower priced motherboard such as this in order to maintain the budget appeal of the processor.

The Athlon-II X2-255, with its 45nm process and low TDP of 65W, is an excellent overclocker. The X2-255 is not a black edition processor, so we were working with a locked multiplier of 15.5. We could lower the multiplier through the BIOS, but not increase it. Even so, just using the bus speed and voltage, we were able to get the Athlon-II X2-255 to 3.8GHz cooled only with air. This represents nearly a 23% increase in the clock speed of the X2-255. We were able to reach 4.0GHz as well, but the stress testing proved to be too much and the processor failed at that level. With some more tweaking, it will likely be possible to reach a stable 4.0GHz, as it took over 9 hours of stressing to cause the Athlon-II X2-255 to fail at that speed.

AMD's ADX255OGQBOX retail kit is available online for only $74.99, which means the Athlon-II X2-255 is priced to sell. While enthusiasts and hard-core gamers will find that the X2-255 doesn't offer the frame rates they desire, any user working with a computer that is over a couple of years old will find that the Athlon-II X2-255 offers an amazing bang for the buck. While the Athlon-II X2-255 doesn't have the L3 cache offered by the Phenom processors, it still outperforms similarly priced Intel process as we saw in most of the tests against the Pentium Dual Core E5300.

Pros:

Cons:

- No notable flaws

Ratings:

• Performance: 9.0
• Construction: 9.5
• Functionality: 9.5
• Overclock: 9.25
• Value: 9.5

Final Score: 9.35 out of 10.

Excellence Achievement: Benchmark Reviews Golden Tachometer Award.

Questions? Comments? Benchmark Reviews really wants your feedback. We invite you to leave your remarks in our Discussion Forum.

Related Articles:

• EonNAS 1100 NAS Network Storage Server
• Gunnar Optiks Shredder Digital Eyewear
• OCZ Vendetta 2 HDT CPU Cooler OCZTVEND2
• AMD FX-8350 Vishera Desktop Processor
• Belkin F5D8053 Wi-Fi N Wireless Adapter
• Gigabyte Ghost Xtreme GM-M8000X Gaming Mouse
• TRENDnet TEW-691GR 450Mbps WiFi-N Router
• OCZ Core Series SATA-II SSD OCZSSD2-1C64G
• Genius HS-03U USB Gaming Headset
• Antec P280 ATX Mid Tower Computer Case