AMD turns heat on Intel with Athlon 64 FX

On the back of AMD's recent launch of Athlon 64 3400+, Intel has confirmed it might launch its 3.4GHz ExSpensive Edition of the XEON MP on the 2nd February, but as the quarter runs on, once again AMD will be turning up the heat on the high-end just that little bit more when it introduces its next Athlon 64 FX. Whilst we all know the next Athlon 64 FX model number is ‘53', is set to operate at 2.4GHz and, as we previously reported, will be available in both Socket 940 and 939 pin packages, we can now reveal that, for both of these sockets, the plot is to dispense with the requirement for the slightly slower, but rather more expensive buffered DDR.

The transaction overhead with Registered DDR is reported to be some 2-3%, but it additionally introduces further challenges when overclocking, so when Athlon 64FX 53 ships, not only will it leverage the anticipated performance lead for AMD, but using unbuffered DDR should make for a better overclocker for the PC enthusiast market too, a market AMD has been keen to retain its hard won dominance over.

There are cost implications here as well because, also as previously reported in the same article, not only will the Socket 939 mainboards - that should start to come available with the launch of Athlon 64FX 53 - be constructed of cheaper, 4-layer PCB's as opposed to the Socket 940's 6-layer PCB requirement, but unbuffered DDR is significantly cheaper than Registered DDR too.

One thing that's not hot though is the relatively low maximum thermal power of Athlon 64 FX 53, which at 89W is so much less of a problem for system builders than the 150W or so the 3.4GHz Extreme Edition P4's is rumoured to generate. Intel is accustomed to quoting only nominal thermal power values for its processors, whilst AMD tell the whole story and quote the maximum thermal power that requires dissipation.

The bottom line is that an expensive BTX form factor chassis won't be a prerequisite even for Athlon 64 4000+ or the 2.6GHz Athlon 64 FX 55, as they are set to have a maximum thermal power of 105W, which is significantly less than the current 3.2GHz P4 Extreme Edition (110.8W).

An Athlon 64FX 51 based on the ‘Sledgehammer' core (as featured in the AMD Opteron) was probably the only viable solution for a concurrent launch of both Athlon 64 and Athlon 64 FX last September, so the forthcoming arrival of the Athlon 64 FX 53 supporting unbuffered DDR has been speculated as being a ‘true' ‘Clawhammer' (like the current Athlon 64 3400+ of the same frequency) but our understanding is that it's a trick rework of the ‘Sledgehammer' core… despite, it seems, what AMD's Desktop Roadmaps might imply. µ