AMD Athlon II X4 640 Processor Review

ajmatson - 2010-05-06 05:26:24 in CPU's
Category: CPU's
Reviewed by: ajmatson   
Reviewed on: May 10, 2010
Price: $122.00


Between the top CPU manufacturers, AMD has been producing a lot of chips over the past year or so. This allows the consumer to choose exactly what is right for them, based the processor's speed and their budget. The Athlon II and Phenom II series have been causing quite a stir in the market due to their low prices, which make them a great bang for the buck. Less than a month ago, we saw AMD drop a six core processor for just under $300, making it quite attractive when compared to the price tag of Intel's six core i7 980X, which retails for around a grand. With a bit of tweaking on the same silicon as the X4 635, AMD has been able to squeeze a bit more performance the Athlon II X4 640, which has a 100MHz higher clock than the 635. This increase in speed will give a bit more performance to those wanting to get the bang for their buck. At launch, the AMD Athlon X4 640 will retail for around $122, making it an inexpensive quad core for gamers and HTPC builders alike.


Closer Look:

There is no physical change to the AMD Athlon II X4 640 as far as the looks go, the difference is under the hood. Here, AMD took their Athlon II Quad Core silicon and found some more speed by bumping up the multiplier up by a half, giving the CPU a 100MHz increase to take its place as the top Athlon II X4 processor. This increase also has allowed AMD to drop the price of the older Athlon II X4 635 to sub $100 prices. This makes the Athlon II X4 series quite tasty for those wanting a high performance, low cost chip. The Athlon II X4 640 uses an increased multiplier of 15x, with the base clock of 200MHz . This is where the 640 gets its 3.0GHz rated speed. All of the other specifications remain the same, this includes: HyperTransport 3.0 support, 45nm manufacturing process, and AM3 desig. The Athlon II X4 640 still has the same L1 cache of 64KB on each core for data and instructions and a L2 cache of 512KB per core, for a total L2 cache size of 2MB. Other features still include AMD Cool 'n' Quiet 3.0, AMD Balanced Smart Cache, and Direct Connect Architecture.










Now that we have seen the physical aspects of the AMD Athlon II X4 640, we can dive into its performance.



Model Number:
Athlon II X4 640
Clock Frequency:
Max TDP:
95 watts
Cache Size:
L1 Cache 64K (each for Instruction + Data)
L2 Cache: 512KB per core (2MB Total)
Process Technology:
45-nanometer SOI (silicon-on-insulator) technology
HyperTransport Technology Links:
One 16-bit/16-bit link @ up to 4.0GHz full duplex (2.0GHz x2)
Integrated 128-bit wide memory controller with speeds: Up to 2.0GHz with Dual Dynamic Power Management
Types of Memory:
support unregistered DIMMs up to PC2-8500 (DDR2-1066MHz) -AND- PC3-10600 (DDR3-1333MHz)
Die Size:
45nm = 169mm2
Socket AM3 - 938-pin organic micro Pin Grid Array (micro-PGA) (Backwards compatable with AM2+ 940-pin)






To test the AMD Athlon II X4 640, I subjected it to a series of strenuous benchmarks that stress the components to their peak. The benchmarks consist of both scientific calculation tests and video tests that push either the CPU or the system as a whole to see how well it stands up under pressure. I then compared the scores to a number of other processors on the market, ranging from dual core processors to the latest hex core processors. I also compared the X4 640 against the Athlon II X4 635 so that you can get a look at how the extra bump in speed makes much of a difference. All of the hardware was tested using the stated speeds, timings, and voltages for each test.



Testing Setup AMD Six Core:


Testing Setup AMD Six Core:


Testing Setup: Intel Core i7 Socket 1366


Testing Setup: Intel Core i5/i7 Socket 1156


Comparison CPUs:



Overclocked settings:

Since the Athlon II X4 640 is not a "Black Edition" with an unlocked multiplier, overclocking the system requires adjusting the voltage and the reference clock speed. Since I wanted to find the most stable highest overclock, I pushed the voltage up to 1.44v, which is where I knew I was safe especially under water cooling. I then pushed up the reference clock 10MHz at a time, adjusting the memory divider and HyperTransport divider at the same time, keeping them at stable speeds. I was able to boot into the computer at 260MHz on the reference clock however; it would not remain stable. I backed down the reference clock a little bit at a time until I was able to pass Prime95 for an hour with no issues. The final speed on the reference clock was 251MHz, which gave me a clock speed of 3.767GHz or 251MHz x 15 at 1.44 volts. During the one hour stability test, the maximum temperature the processor reached was only 53°C, which is way below the rated 71°C maximum which makes it a very safe overclock.





Maximum Clock Speeds:

Each CPU has been tested for stability at the clock speeds listed when in an overclocked state. These clock speeds will represent the overclocked scores in the testing.




  1. Apophysis
  2. WinRAR
  3. Office 2007 Excel Number Crunch
  4. POV Ray 3.7
  5. PCMark Vantage Professional
  6. Sandra XII
  7. ScienceMark 2.02
  8. Cinebench 10 & 11.5
  9. HD Tune 3.50
  1. Far Cry 2
  2. Call of Duty Modern Warfare 2
  3. Batman Arkam Asylum
  4. 3DMark Vantage


The first part of our testing will be the system specific benchmarks.


Let's get started with Apophysis. This program is used primarily to render and generate fractal flame images. We will run this benchmark with the following settings:



The measurement used is time to render, in minutes, to complete.











Lower is Better


WinRAR is a tool to archive and compress large files to a manageable size. We will use 100MB and 500MB files to test the time needed to compress these files. Time will be measured in seconds. Additionally, I will use the built in benchmark as a comparison.





Lower is Better





Lower is Better


In all of the tests here, the Athlon II X4 640 showed improvement over the Athlon II X4 635 it replaces. It still isn't as fast as some of the higher end quad core processors with larger cache.


Office 2007 Excel Big Number Crunch: This test takes a 6.2MB MIcrosoft Excel speadsheet and performs about 28,000 sets of calculations that many of the most commonly used calculations in Excel. The measure of this test is how long it takes to refresh the sheet.

















Lower Is Better


POV Ray 3.7: This program features a built in benchmark that renders an image using Ray Tracing. The latest versions offer support for SMP (Symetric MultiProcessing) enabling the workload to be spread across the cores for a quicker completion.


Higher Is Better


PCMark Vantage x64 is used to measure complete system performance. We will be running a series of tests to gauge performance of each individual CPU to see which CPU, if any, rises above the others.




Geekbench 2.1 provides a comprehensive set of benchmarks engineered to quickly and accurately measure processor and memory performance. Designed to make benchmarks easy to run and easy to understand, Geekbench takes the guesswork out of producing robust and reliable benchmark results.



In the POV Ray testing, the X4 640 again was the fastest Athlon II. In the rest of the tests, it remained the fastest Athlon II, but not as fast as the other quad cores.


SiSoft Sandra is a diagnostic utility and synthetic benchmarking program. Sandra allows you to view your hardware at a higher level to be more helpful. For this benchmark, I will be running a broad spectrum of tests to gauge the performance of key functions of the CPUs.
















Processor Arithmetic




Multi-Core Efficiency




Memory Bandwidth




Memory Latency



Cache and Memory




File System




Physical Disks


Power Management Efficiency



As before, the Athlon II X4 640 keeps its reign as the fastest Athlon II, but the higher end quad cores are just to fast for it to keep up.


ScienceMark tests real world performance instead of using synthetic benchmarks. For this test, we ran the benchmark suite and will use the overall score for comparison.


















Higher is Better


CineBench 10 is useful for testing your system, CPU, and OpenGL capabilities using the software program CINEMA 4D. We will be using the default tests for this benchmark.



Higher is Better


CineBench 11.5 is the latest iteration of this popular benchmark that features a new look to the interface. This test now has a simple GPU and CPU test built in.


Higher is Better


HD Tune measures disk performance to make comparisons between drives or disk controllers.



Higher is Better




Lower is Better


Throughout these tests as well, the Athlon II X4 640 is between the other Athlon II's and the rest of the test processors.


Far Cry 2:

Featuring a new game engine named Dunia, this game looks to be another one to stress your video card. Built especially for Far Cry 2, this engine allows for real time effects and damage. This next generation First Person Shooter comes to us from Ubisoft surprisingly - not from Crytek. The game is set in a war-torn region of Africa where there is a non-existent central government and the chaos that surrounds this type of social environment. If you have seen the movie Blood Diamond, you know the setting. Ubisoft puts the main storyline of the game into focus with these statements: "Caught between two rival factions in war-torn Africa, you are sent to take out "The Jackal," a mysterious character who has rekindled the conflict between the warlords, jeopardizing thousands of lives. In order to fulfill your mission you will have to play the factions against each other, identify and exploit their weaknesses, and neutralize their superior numbers and firepower with surprise, subversion, cunning and, of course, brute force." In this version of the game, you don't have the beautiful water, but instead the beauty and harshness of the African continent to contend with. Most games give you a set area that can be played through, while Ubisoft has given the gamer the equivalent of 50km squared of the vast African continent to explore while in pursuit of your goals. The settings used are just a few steps below the maximum in-game settings and offer a good blend of performance vs. visual quality.
















While slower than the higher end chips, all of the Athlon II's were almost dead on with each other.


Call of Duty: Modern Warfare 2 is the latest iteration of the venerable first-person shooter series, Call of Duty. Despite its long, successful pedigree, the game is not without substantial criticism and controversy, especially on the PC. Aside from the extremely short campaign and lack of innovation, the PC version's reception was also marred by its lack of support for user-run dedicated servers, which means no user-created maps, no mods, and no customized game modes. You're also limited to 18-player matches instead of the 64-player matches that were possible in Call of Duty 4: Modern Warfare. Despite all this, the game has been well received and the in-house IW 4.0 engine renders the maps in gorgeous detail, making it a perfect candidate for OCC benchmarking. You start off the single player missions playing as Private Allen and jump right into a serious firefight. This is the point where testing will begin. Testing will be done using actual game play with FPS measured by Fraps.

















For Modern Warfare 2, the Athlon II X4 640 takes the lead of the Athlon II processors, but is still behind the higher end CPUs.


Batman: Arkham Asylum is a new game that brings together two bitter foes, The Joker and Batman. The Joker Has taken over Arkham Asylum, Gotham's home for the criminally insane. Your task is to rein the Joker back in and restore order. This game makes use of PhysX technology to create a rich environment for you to ply your trade.




















In Batman, the Athlon II X4 640 has a bit of a lead over the other Athlon II processors.


Featuring all-new game tests, this benchmark is for use with Vista based systems. "There are two all-new CPU tests that have been designed around a new 'Physics and Artificial Intelligence-related computation.' CPU test two offers support for physics related hardware." There are four preset levels that correspond to specific resolutions. 'Entry' is 1024x768 progressing to 'Extreme' at 1920x1200. Of course, each preset can be modified to arrange any number of user designed testing. For our testing, I will use the four presets at all default settings.
















Again the Athlon II X4 640 has a slight advantage over the other Athlon II processors.


When it comes to the bottom line, the AMD Athlon II X4 640 takes the lead for the Athlon II series processors with its increase in speed. Even with only a 100MHz increase, the Athlon II X4 640 has the edge it needs to sneak in as top dog. Now here is the quirky part. The Athlon II X4 640 is essentially an Athlon II X4 635 with an increase in the multiplier by a half. So is it worth it  to pay a bit more for the X4 640, when you can just overclock the X4 635 by raising the multiplier to 15x? Well this all depends on your usage of the processor. If you are just buying it for a workstation or HTPC, then I would opt for the Athlon II X4 635, which will be dropping to sub $100 pricing with the release of the Athlon II X4 640. 

Now, if you already have the last generation Athlon II X4 635, then I suggest you keep it. It's not worth paying extra for a little performance increase. Now if you are looking for a solid, low cost, quad core for your HTPC or workstation, then you cannot go wrong with the Athlon II X4 640 processor. At that price, you could build a complete system for what one of the more "high end" CPUs go for. However, if you want an easy to achieve, stable overclock as well as excellent performance for the price, then the Athlon II X4 640 at a low $122, is the CPU for you.