We get a lot of reports that our game won't display our menus on computers with Rage 128 Pro cards (and Rage fury cards which use the same chipset), on both Mac and PC. This boils down to our GUITextures rendering all white on those cards. I don't know if other textured geometry is correctly rendered. Has anyone had any experience with GUITextures working or not working on Rage cards? Thanks.
I'm betting that you're just running out of VRAM, which is hardly surprising since those cards only have 8 or 16MB VRAM to play with. You'll probably have to reduce the resolution of your textures and/or get the user to select a lower screen resolution to make it work. You might also find that you can't realistically support those cards at all.