Since on Athlon 64 who controls memory access is the CPU and not the chipset, it is very interesting to compare the memory performance between AMD and Intel CPUs.

This test was done with the aid of Sandra 9.89 program and the results, shown on the graph below, are in MB/s. Since we used two DDR400/PC3200 modules, the maximum theoretical performance of this memory was 3,200 MB/s in single channel and 6,400 MB/s in dual channel. We included these rates on the chart below for comparison.

The embedded memory controller on Athlon 64 processors are far better than memory controllers located on the chipset, allowing the memory transfer rate finally go near the theoretical 6,400 MB/s DDR Dual Channel transfer rate. Athlon 64 FX-57 achieved a 5,728 MB/s transfer rate, using 89.50% of the available bandwidth.

To understand what this number means, the Intel CPU that reached the best memory access performance was Pentium 4 3.2 GHz “E” (“Prescott”), with a 4,889 MB/s transfer rate, a 76.39% use of the available bandwith (Athlon 64 FX-57 acessed RAM memory 17.16% faster than this processor).

Funny enough, the memory performance of Athlon 64 FX-57 was lower than all other socket 939 processors we’ve tested.