AMD has finally released the Socket 939 version of their Athlon64 processors, which includes the Athlon64 FX53 (Socket 939), the Athlon64 3800+ and the Athlon64 3500+ with the two latter running the dual memory controller but being restricted to the smaller 512 kB L2 cache of the Newcastle die. However, the entire family of Socket 939 processors is capable of running unbuffered memory, which shaves off one bus cycle on each initial memory access.

Aside from the price advantage over the Socket 940 processors, is there any gain in performance caused by the lower latency memory access? Moreover, does the cache reduction hurt the performance and if so, what are the critical applications?

We have looked at the performance of the new platform from a variety of different angles, including different memory configurations that can make quite a difference. After all, AMD processors are more dependent on low latency memory and, by extension, on open pages..