Texture antialiasing
To test texture filtering, I used Quake III Arena's timedemo function at 1600x1200 resolution with various filtering settings.

The GeForce FX runs Quake III especially well, so it has a bit of advantage here in overall performance. In terms of scaling, there aren't many surprises, either. The FX takes a little more of a performance hit with trilinear filtering than the GeForce4 does, but it's so much faster overall, no one will complain.

Incidentally, I used the "Quality" setting in the NVIDIA "Performance & Quality Settings" control panel throughout my performance testing. There are two other options, "Application" and "Performance". Let's take a look at what the three settings do.

Below are some low-compression JPEG images from Quake III that show the effects of the various filtering settings. You can click the images to see full-quality PNG versions. I've arranged the screenshots from highest quality filtering to lowest, and the difference is very visible in the look of the textures in the scene, especially in the long bridge surface stretching out in front of the viewpoint.

GeForce FX "Application" option: 8X aniso + trilinear filtering

GeForce FX "Quality" option: 8X aniso + trilinear filtering

The difference between "Application" and "Quality" is difficult to see with the naked eye, but you can tell by looking at the definition of the seams between the tiles underneath the railgun, if you look closely. (The railgun is in the player's weapon sights, floating above that little platform there.) The definition of textures is cleaner with "Application," even right up next to the viewpoint.

GeForce FX "Performance" option: 8X aniso + trilinear filtering

I'm not sure how NVIDIA can call the "Performance" option 8X anisotropic filtering. The number of samples here is obviously lower, and there's visible banding along the Z axis as the eye scans up the platform. The tile seams under the railgun are no longer distinct.

GeForce FX Standard isotropic filtering (bilinear + trilinear)

I included this sample of trilinear + bilinear filtering to show you how little difference there is between this filtering mode and the "8X" "Performance" option. Compare this image to the one at the top of the group to see how much difference anisotropic filtering can really make.