Following http://en.uesp.net/wiki/Redguard:Technical_Tips_and_Hacks I downloaded the v1.02.03 voodoo banshee drivers and copied the glide files into the Redguard directory.

This fixed the texture glitches with the V3 in 3dfx mode but for some reason if I set the game resolution to 1280x1024 or 1600x1200 the game will run at 640x480 when launched. 800x600 and 1024x768 seem to work without any issue. I've read that while installed and launched through Windows Redguard actually plays through DOS. This might account for why 1600x1200 reverts because my monitor won't do that resolution over VGA without the powerstrip customization being recognized (desktop is 1600x1200 no problem in Windows) however 1280x1024 worked just fine in other DOS games.

Could it be the glide files? Are there better ones to use with the V3 over the 1.02.03 banshee ?