AMD's FX Series

The Athlon 64 FX is the most powerful device in the AMD64 processor family - and its $1,000 per-unit cost also makes it the most expensive. In consideration of the price, customers get a slightly higher clock speed and the option to overclock the processor with the device's free multiplier selection capability. However, given the price, we only recommend investing in the device when maximum CPU power is required for very high-end - and almost always professional - computationally-intensive tasks.

AMD initially made only one FX model available. The Athlon 64 FX-51 (2.2 GHz) was the first version, but it was only available for Socket 940. Athlon 64 FX-53 (2.4 GHz) followed with the introduction of the Socket 939 platform, and it was replaced by the FX-55 (2.6 GHz). However, it was not phased out when the 2.8 GHz Athlon 64 FX-57 was released. According to AMD, demand existed for two different FX versions.

We assume that the FX-57 will still be around for some time following the introduction of the FX-60, since its clock speed makes it the fastest single-thread processor available from AMD. Also, some applications run marginally slower on dual-core processors compared to their single-core counterparts with the same clock speed (we found a 3.3% difference with WinRAR, for example). Yet this advantage will be short lived as more applications make use of thread-optimized multiple processing cores.

So why has AMD waited so long before launching a dual-core FX? AMD claims that the market was not ready, demonstrated by the lack of applications that could benefit from a second-processor core. However, AMD really believes that a dual-core FX premium processor should not be considerably slower than a single-core device, even in single-threaded environments. For AMD, it would be unacceptable for any dual-core device to run more slowly than a single-core CPU.