Texture filtering
Generally, I'll show all the cards on a test like this, but this time around, I decided to include results from the GeForce 6800 Ultra using the 60.72 drivers. Since the 61.11 drivers don't disable trilinear optimizations properly, the results wouldn't show what I'd like. Instead, you can see results from the 60.72 drivers for the GeForce 6800 Ultra using three modes: the regular results without trilinear optimizations, with NVIDIA's "brilinear" optimizations enabled, and with the "high quality" anisotropic filtering option checked. Note, also, that I'm testing in Direct3D mode here, not OpenGL, since Direct3D is more commonly used for games nowadays.

The top-end cards are nearly impervious to texture filtering loads in Serious Sam, especially the Radeon X800 XT PE. Overall, though, most of the cards scale fairly similarly. You can see how the "brilinear" mode helps the GeForce 6800 Ultra's performance when anisotropic filtering is in use.