DX8.1

GeForce FX 5950 DX9

Once DirectX 9 is enabled, GeForce FX cards took a significant performance hit in our testing. For GeForce FX 5700 Ultra and 5600 Ultra, we witnessed performance declines of up to 2.5 times running the DirectX 8.1 path in a couple of cases with the video stress test. In comparison, RADEON 9600 XT's worst-case scenario was a performance decline of 23% at 1600x1200 with 4xAA and 8xAF. On the high-end cards, GeForce FX 5950 Ultra performance dropped by a factor of two once the DirectX 9 path was enabled (versus RADEON 9800 XT's 10-27%). Essentially, enabling the DX9 path with GeForce FX cards knocks your frame rate in half with Valve's video stress test, the performance dropoffs are sometimes even worse for GeForce FX in Counter-Strike: Source beta. Just take a look at the trilinear benchmarks on page 7. It isn't pretty for GeForce FX at 1024x768 and 1280x1024 with the DX9 path enabled.