I've had this home-built gaming and web-browsing only PC for a couple of years - no hardware changes 9CJS 9600XT 1 gig Corsair RAM (4 x 256) Sound blaster Live WD 120G HD Lite-On CDRW CBox3 onboard NIC (Realtek 10/100) A few weeks ago it started to reboot during shutdown. I first noticed because it would be on every morning after a scheduled night time defrag (I wasn't gaming during that time period due to external issues). It would also not shutdown when I turned it on manually. As far as I remember the only "new" things done around the time this started was the frequent updating by Microsoft for XP :-( When I turned off the 'auto-reboot on failure' switch I saw kernal related faults(tracked down at websites for XP stop codes) that every website, including Microsoft, said were 99% likely to be caused by hardware drivers. I have updated to the latest BIOS (ver 8), video driver from ATI, sound drivers from Creative, Windows XP default drivers for my Lite-On CDRW per Lite-On recommendations, ran SpyBot Search and Destroy, Adaware, latest Norton anti-virus, and cleaned my registry. The only drivers I didn't update were the mainboard drivers because I felt the instructions sucked. If I shutdown from Safe Mode it goes okay. However, if I did a Selective Start-up (MSCONFIG) and unchecked EVERYTHING the system would hang up on shutdown again. The stop code might be different (depending on what items I unchecked) but it was always a kernal related code. Any suggestions other than a re-install? Would disabling things in the Hardware tab allow me to isolate the offending driver?