X-bit labs

AMD Athlon 64 3800+ CPU: E3 Processor Core aka Venice at the Door (page 8)

Category: CPU

by Ilya Gavrichenkov

[ 04/03/2005 | 04:06 PM ]

Performance

The SuperPi benchmark, which is very popular among computer enthusiasts, shows clearly that Venice core is faster than Winchester. However, I have to stress that the performance increase we observe here is not that great and hardly exceeds 0.5%. Anyway, nobody promised anything significant here: the memory controller in the Venice core got just a little bit better, and the discussed SuperPi test doesn’t use SSE3 instructions at all.

Here I have to clarify that there is an unofficial patch for SuperPi benchmark, which involves FISTTP instruction from SSE3 set into its calculations. Once you run this patch, the calculation of 8M digits of the pi-value on Athlon 64 3800+ (Venice) will take 375 seconds instead of 385, which is about 2.5% faster than same calculation speed without SSE3 patch.

The results of the FutureMark PCMark04 allow us to draw similar conclusions. The advantage of the new Venice core over the Winchester doesn’t go beyond 1% all the time.

3DMark2001, which has long become more of a CPU test rather than graphics accelerator test, is also showing the same results as the previous benchmarks. Venice based CPUs are again faster than Winchester based ones, and again this advantage is relatively small.

But in the newer 3DMark05 Athlon 64 3500+ with D0 core stepping appears faster than the same CPU on the E3 core stepping. So, it looks like the improvements of the Venice memory controller may sometimes have reserves effect. In fact, the processor performance increased much more on the transition from Newcastle to Winchester core, than on the transition from Winchester to Venice. In other words, the enhancements of the Winchester memory controller were much more global than those of the current Venice memory controller. This is our judgment so far, because we haven’t yet discussed the performance in applications using SSE3 instructions.

CPU performance index from the same FutureMark 3DMark05 reveals more significant dependence of the results on the processor core optimizations. According to the benchmark numbers, Venice is about 4.7% faster than Winchester.