Hi, my PC is a Pentium 4 2.0A GHz with 256MB ram, etc. Lately, the PC keeps restarting for no reason. It keeps restarting at the POST screen, or even when I'm in BIOS. If I am really lucky, I can get to the Windows XP desktop, only for it to restart. I have ruled out the HDD, as a faulty HDD won't be a culprit for restarts at the POST screen. I have changed the power supply and the power outlet to which the PC is plugged into. I don't see any "swollen" or "bloated" capacitors on the motherboard, and I have replaced the RAM with a new stick. Sometimes when the PC restarts, the monitor doesn't detect anything, the USB mouse light will be 'ON' and the NUM lock light will be lighted and jammed for a long time. I suspect the culprit is the mobo, or the CPU itself. Any suggestions and advice will be much appreciated. Thank you!