Processors

AMD Opteron 254

The Opteron 254 is the senior model in the single-core CPU series meant for dual-processor systems. AMD has just recently started to ship such CPUs. The Opteron 254 is based on the 90nm Troy core which is in fact an analog of the San Diego core employed in Athlon 64 FX and Athlon 64. In other words, the Troy is the same E4 stepping, supports SSE3 and features a 1MB L2 cache.

The Opteron 254 processors we got for our tests were marked as OSA254FAA5BL and this is actually the only existing version of the Opteron 254. Having a very high clock rate of 2.8GHz, this processor doesn’t have a reduced-heat-dissipation modification. The TDP of the Opteron 254 is 92.6W, so it can be used with the same mainboards as other CPUs from the Opteron family.

The relatively low heat dissipation is one of the differences from the Athlon 64 FX-57 which too works at 2.8GHz and has a 1MB L2 cache, but has a TDP of 104W (or 12% higher). It means that AMD has to cull the semiconductor dies more carefully to produce the Opteron 254.

The other points of difference between the Opteron 254 and the Athlon 64 FX-57 are in fact the generic differences between the respective series. The Opteron 254 is meant for dual-processor systems, is installed into Socket 940, has an integrated dual-channel memory controller that requires registered modules of DDR SDRAM, and features three HyperTransport buses (rather than one) to connect to the chipset and to the second CPU.

The formal specification of the processor is listed below:

This is the information the diagnostic CPU-Z utility reported about our sample of AMD Opteron 254:

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We built a classic dual-processor system using two such CPUs. The Opteron 254 is neither physically nor virtually a dual-core processor, so the computer with two such CPUs was identified by the OS as having two logical processors.