The single pass multitexturing capabilities of the Ultra TNT2 are no doubt an eyebrow raiser in terms of the performance. It works the same way as 3Dfx's in that it renders a light map over a textured scene all in a single pass (see below):

Texture

+

Lightmap

=

Image

No we won't address the issue of the ongoing multi texturing patent dispute but what we will address is the pure and simple fact that nVIDIA has clearly done something right in terms of technology. Their TwiN Texel engine, which enables their single pass multi-texturing wasn't really being used efficiently on their original TNT due to the lower clock speeds limitations (original TNTs are clocked at 95-105MHz). But the Ultra TNT2s clock speed is way higher (see below) now and thus Quake 2 now performs as it should. Meaning always above 60 frames per second (except at 1600x1200 of course). The OpenGL support has always been good seeing as nVIDIA has long supported a full ICD.