I can only render up to 4 pixels per clock with NV3x cards (tested with Quadro FX 2000 and GeForce FX 5900 Ultra). I’m using my own little glut benchmark program, which just renders simple polygons, untextured or with a 2D texture.
On a ATI FireGL X1 card with 325 MHz, I expect up to 8 x 325 = 2600 MPixel/s and the benchmark shows 2462 MPixel/s. With the FX 5900 Ultra I get only less than 4 x 450 MHz = 1800 MPixels/s, exactly half of the expected 3600 MPixels/s.
I heard that the FX cards can only do 4 color and 4 Z operations in one pass, but 8 texture operations. I switched off the depth test and I don’t need the color of the fragment, I only need the result of the texture lookup (GL_REPLACE). Is it possible to render more than 4 pixels per clock with these restrictions?
Or is there ANY program that proves the existance of the “8 pixels per clock rendering engine” (from http://www.nvidia.com/docs/lo/2692/SUPP/NV_QuadroFX_0306.pdf)??) Any program that renders somehow more than 4 pixels per clock?