After posting on here a while ago that my computer (Dell 4300 w/XP Home SP2) was rebooting approximately 3 times a day. Most replies pointed me towards the power supply. I did the calculations and because of the items I've added (2nd hard drive, dvd burner, usb 2.0), my power supply was certainly being taxed. I upgraded the old 250W to a 500W. The problem is still there. About every 8 hours or so it will reboot, no matter what I am doing, or not doing. There are no other symtoms whatsoever. So I am wondering where to start looking from here. Can anybody help?