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CPU Core Details

CPU Codename Callisto Deneb
MoBo Socket Socket AM2+ / AM3 Socket AM3
Notebook CPU no no
Release Date 01 Jan 2011 02 Jun 2009
CPU Link GD Link GD Link
Approved

CPU Technical Specifications

{
CPU Cores 2 4
CPU Threads 2 4
Clock Speed 3.4 GHz 2.5 GHz
Turbo Frequency - -
Max TDP 65 W 65 W
Lithography 45 nm 45 nm
Bit Width 64 Bit 64 Bit
Max Temperature - 70°C
Virtualization Technology no no

CPU Cache and Memory

L1 Cache Size 256 KB 64 KB
L2 Cache Size 2048 KB 2048 KB
L3 Cache Size - 6 MB
Memory Types
Memory Channels 2 2
ECC Memory Support no no

CPU Graphics

Integrated Graphics no no
Base GPU Frequency - -
Max GPU Frequency - -
DirectX - -
Displays Supported - -

CPU Mini Review

Mini Review Phenom II X2 511 is a middle-class processor based on the 45nm, K10 architecture. <br/> <br/> It offers 2 Physical Cores (2 Logical), clocked at 3.4GHz and 2MB of L2 Cache. <br/> Among its many features, <b>Virtualization</b> is activated. <br/> <br/> The processor DOES NOT integrate any graphics. and has a rated board TDP of 65W. <br/> <br/> It offers average performance. This means it will become a bottleneck in some demanding applications. Phenom II X4 905e is an energy efficient processor based on the 45nm, K10 architecture. <br/> <br/> It offers 4 Physical Cores (4 Logical), clocked at 2.5GHz and 6MB of L3 Cache. <br/> Among its many features, <b>Virtualization</b> is activated and the clock multiplier is unlocked, meaning it can be overclocked easily. <br/> <br/> The processor DOES NOT integrate any graphics. and has a rated board TDP of 65W. <br/> <br/> It offers average performance. This means it will become a bottleneck in some demanding applications.

Gaming Performance Comparison

In terms of overall gaming performance, the AMD Phenom II X4 905e is massively better than the AMD Phenom II X2 511 when it comes to running the latest games. This also means it will be less likely to bottleneck more powerful GPUs, allowing them to achieve more of their gaming performance potential.

Both the Phenom II X2 511 and the Phenom II X4 905e were released at the same time, so are likely to be quite similar.

The 4 has 2 more cores than the Phenom II X2. { With 4 cores, the 4 is much less likely to struggle with the latest games, or bottleneck high-end graphics cards when running them.

The Phenom II X4 has 2 more threads than the Phenom II X2. Both CPUs have one thread per physical core.

Multiple threads are useful for improving the performance of multi-threaded applications. Additional cores and their accompanying thread will always be beneficial for multi-threaded applications. Hyperthreading will be beneficial for applications optimized for it, but it may slow others down. For games, the number of threads is largely irrelevant, as long as you have at least 2 cores (preferably 4), and hyperthreading can sometimes even hit performance.

More important for gaming than the number of cores and threads is the clock rate. Problematically, unless the two CPUs are from the same family, this can only serve as a general guide and nothing like an exact comparison, because the clock cycles per instruction (CPI) will vary so much.

The Phenom II X2 and Phenom II X4 are not from the same family of CPUs, so their clock speeds are by no means directly comparable. Bear in mind, then, that while the Phenom II X2 has a 0.9 GHz faster frequency, this is not always an indicator that it will be superior in performance, despite frequency being crucial when trying to avoid GPU bottlenecking. In this case, however, the difference is probably a good indicator that the 4 is superior.

Aside from the clock rate, the next-most important CPU features for PC game performance are L2 and L3 cache size. Faster than RAM, the more cache available, the more data that can be stored for lightning-fast retrieval. L1 Cache is not usually an issue anymore for gaming, with most high-end CPUs eking out about the same L1 performance, and L2 is more important than L3 - but L3 is still important if you want to reach the highest levels of performance. Bear in mind that although it is better to have a larger cache, the larger it is, the higher the latency, so a balance has to be struck.

The Phenom II X2 and the Phenom II X4 have the same L2 cache size, but the Phenom II X2 does not appear to have an L3 cache, so the Phenom II X4 definitely wins out in this area.

The maximum Thermal Design Power is the power in Watts that the CPU will consume in the worst case scenario. The lithography is the semiconductor manufacturing technology being used to create the CPU - the smaller this is, the more transistors that can be fit into the CPU, and the closer the connections. For both the lithography and the TDP, it is the lower the better, because a lower number means a lower amount of power is necessary to run the CPU, and consequently a lower amount of heat is produced.

Both the Phenom II X2 and the Phenom II X4 have the same TDP of 65 Watts, and were created with the same manufacturing size of 45 nm, which means they will affect your yearly electricity bill about equally.