I'm working on a Win Xp Home edition PC for one of my customers and the machine keeps rebooting in a continous cycle on startup. There are several topics on these pages relating to the rebooting cycling but none of them (that I've read) specifically address my symptoms exactly. I've tried to boot in safe mode; used repair feature in recovery console including copying files from the windows repair folder; booting to last known good config, and several other tricks posted on this web site, all without any luck I finally put another hard drive with a 'clean' version of XP into the machine, made it the primary boot drive and made the 'troubled' drive the slave. With this setup the machine boots up without a single problem. Fans (CPU and power supply) are running fine and nothing appears overly hot inside the box. I replaced the memory just for the heck of it. With the machine up and running on the 'temporary' drive I can see the troubled drive, read, copy, move files, folders, etc at will. I ran check disk and every other utility I could think of. My customer tells me that he did not install any new hardware or software prior to ths error and that it first occured when he was surfing the web using AOL (UGH). I'm thinking that my next step is to copy user data files and settings over to the temporary drive and reinstall XP Home on the original drive. Anyone have any other suggestions before I start a re-install?