AMD Athlon 64 3200+ Clawhammer, VIA K8T800, nForce3 150 review
The AMD Athlon 64 FX-51, a CPU that's essentially a rebadged Opteron running at 2.2GHz, is currently gaining a number of plaudits from the reviewing media. 2.2GHz clock speed doesn't sound like an awful lot in a world where Intel's fastest consumer-level CPU has already hit 3.2GHz and shows no signs of abating, but it's not how big your clock is, it's how you use it. Performance, AMD will not tire of telling you, is the sum of pure MHz and the number of instructions completed per clock cycle. AMD's True Performance Initiative seeks to educate the consumer in just this respect. A 1.6GHz Applebred Duron isn't as fast as a 1.6GHz 142 Opteron, yet both run at the same clock speed. Massive architectural differences allow the latter to spank the former in almost every conceivable benchmark.
Let's not get distracted with a moot discussion on the relative merits of Durons and Opterons, though. The AMD Athlon64 FX-51 is a monster performer in most respects, that much has been made plainly clear. However, with its roots very firmly entrenched in the Opteron camp, which is primarily a server / workstation-class CPU, the FX-51's need to use registered memory will no doubt put a number of enthusiasts and gamers off. If that's not enough, the ~ £700 price tag will position it as a CPU limited to those with a penchant for cutting-edge components and extremely deep pockets. To further dampen spirits, stock is in short supply and lower grade FX models are yet to be announced.
Yet hope is very much at hand. The media circus has been circulating around the 940-pin dual memory channel AMD64 FX-51 CPU. AMD, in its wisdom, has not positioned the FX-xx line as the natural successor to the consumer-level Barton CPU. No, that job is left for another 32/64-bit hybrid that takes many of the qualities from the Opteron / FX and amalgamates them into a package that's sure to whet the appetites of enthusiasts and power freaks on a relative budget. If the FX-51 is the Sledgehammer, the 754-pin variety is the Clawhammer. The major difference lies in the way the memory controller communicates with the DRAM. You see, while the Sledgehammer uses dual 64-bit channels linked up to ECC RAM, the Clawhammer forgoes a channel and makes use of regular unbuffered DRAM. Less bandwidth but more DRAM compatibility, it seems. Let's try to get to the bottom of the confusing Hammer family.