Hieronder de info en benchmarks, afkomstig van Riva Station:
Benchmarks made on an ASUS AGP-V6800 Deluxe with an Intel Pentium III 700/100:
wooha... more than 10% faster (The 49,9% value seems was wrong.. (I´d doublechecked it... rebooted 2 times and made 3runs per resolution on a fresh w98 inst... but.. hmmm)) with max. Details at 1024x768-32!!! But AGP-Sidebanding with GeForce cards does still not work by default.
For a test with TNT2 I used an ASUS AGP-V3800 Ultra Deluxe:
The increase on TNT2 cards is not as dramatic as with GeForce, but it´s also there at all!
Update: To use the special S3 Quake3 Arena maps with S3TC you need a special EXE file bsides of the maps: DMMQ3.EXE. The levels work without any additional settings with the 5.08 drivers if you start the game with this EXE instead of the normal file. You can download the EXE and levels here: S3 Q3A Levels.