Version 1.1 and 1.4 Pixel Shaders
The same 3DMark 2001 SE helps us to measure the speed of DirectX 8.1 pixel shaders execution. As before, GeForce FX 5800 Ultra is benchmarked at regular and reduced working frequencies.
When working at lower frequencies, GeForce FX executes this simple pixel shader a little slower than RADEON 9700 PRO, but the gap between them is getting smaller in higher resolutions.
At its nominal frequencies, the new card from NVIDIA quite naturally outperforms its rival.
This more complex pixel shader brings a disappointing result: NVIDIA GeForce FX 5800 Ultra loses to ATI RADEON 9700 PRO even working at its regular frequencies. And when working at 325MHz/620MHz, GeForce FX even fell behind GeForce4, which doesn’t have ver.1.4 pixel shaders support and has to render the scene in two passes.
Why is it so? This may be the result of “cutting-down” computational power of the chip: it just doesn’t have enough arithmetic processors. Or the tradeoff for its highest flexibility. Both causes are quite plausible.
Version 2.0 Pixel Shaders
For checking the execution speed of ver.2.0 pixel shaders we took a test from the 3DMark03 suite. This test draws a scene with statuettes of an elephant and rhinoceros on a pedestal. The complex materials the statuettes and pedestal are made of are not textured, but are calculated in real time by means of 2.0 pixel shaders. The shaders use a lot of floating-point calculations.
Most depressing results! NVIDIA GeForce FX 5800 Ultra loses to ATI RADEON 9700 PRO turning out several times slower. This once again proves that NV30 executes advanced and calculations-heavy pixel shaders less efficiently than R300.