Is there a version of GLSetup that will work with WinXP? If not, is there a similar program that is XP compatible?
GLSetup is accient. People usally get the impression that GLSetup installs OpenGL, well it doesnt. Since Win95B all versions of Windows include OpenGL. Unfortunatly the drivers that come with said Windows version only support Microsoft own DirectX but not OpenGL so you need to download the appropriate driver for your ATI (www.ati.com) or Nvidia (www.nvidia.com) chipset based board.
GLSetup is/was a little util that detected what kind of 3d chipset your card was using (3DFX, Rendition, Number9, ATI, S3, Nvidia, Trident, …) and downloaded the appropriate driver for you. As you may have noticed most of the manufacturers in the list above are dead or their market share is not worth mentioning.
GLSetup was last updated (as far as I recall) arund Juli 2001, its discontinued because today 90% of the drivers have proper OpenGL support and the remaining 10% is shared between SiS, Trident, PowerVR and soforth who eighter dont support OpenGL at all or have bugged/incomplete drivers.
GLSetup is obsolete and hence discontinued and no longer supported.