Had that problem before in two different ways. 1: The installation of XP whent finished up to 99% but then a blue screen and reboot and back to pre-install. 2: Installation whent great but after the finishing reboot a black screen and nothing more when Windows starts reading up, bluescreen after reboot with a list of how I whant to start XP (ex. start in fale safe mood). Retailer says there was a HDD problem but was in the end both pixel-error on my graphic card and a bad RAM.
Do you get a bluescreen text that ati2dvag.dll have stuck in a ethernal loop? Then its a Windows error. Good luck