First we tested the EVGA card at its default frequencies, i.e. 450/490/1200MHz. Then we increased the frequencies of the GPU by 9MHz and repeated the tests once again. We selected 9MHz on purpose: if the G70 could only change its frequencies with a discrete 13/27MHz step, then a frequency growth of 9MHz wouldn’t reflect on the performance of the graphics card. Despite the above-mentioned theory, RivaTuner reported the increase of the frequency of the vertex processors to 497.25MHz when we overclocked the EVGA card to 459MHz. We also performed this test on a reference sample of the GeForce 7800 GTX, overclocking it from 430 to 439MHz. And here are the numbers we got:

So in both cases we had a minor performance improvement (about 40-50 points irrespective of the number of times we ran 3DMark) after we had increased the GPU frequency by 9MHz. So, the supposition that NVIDIA’s G70 controls the frequency with a discrete step of 13/27MHz doesn’t come true. If it were true, we wouldn’t have any performance gain at the 9MHz step. But since we do have that gain, it means the new graphics processor from NVIDIA overclocks just like older solutions, except for the fact that the frequency of its vertex processors is always 40MHz higher than that of its pixel pipelines and raster operators.

We also found that the 450 megahertz is the frequency of the pixel processors on the e-GeForce 7800 GTX, so this graphics card should have a small advantage over the regular GeForce 7800 GTX in gaming benchmarks. Unlike some other manufacturers who declare the frequency of the vertex processors (470MHz) as the main one, EVGA honestly specifies 450MHz which is the frequency of the pixel pipelines and ROPs, i.e. the frequency of the units the overall performance of a GPU depends the most on.

As for our overclocking achievements, we got 490MHz on the GPU (530MHz on the vertex processors) and 1380MHz on the memory. We think it is a nice gain, especially for GDDR3 chips that already worked near their limit. We set an additional 120mm fan from A.C.Ryan to blow at the card when we were testing it in the overclocked mode.