This morning my computer won't bootup. It keeps restarting over and over. It will flash the log on screen and restart.

Any messages? Can you boot into safe mode? Try unplugging the network and booting... What happens.. J. j e r u v y a t y a h o o d o t c o m

can you start in safe mode? if yes, download stinger and scan your system Today's subliminal thought is: 'Calm down ... it's only ones and zeros.'

Feel the power supply unit at back of tower after a while! is it overheating?. it may be your problem is a faulty psu hmm i guess so

Are you sure that it is the logon screen that flashes, and not an error message? My puter is doing the same thing except it goes to the "windows did not start properly" message first and then it reboots flashes a message and reboots.

Yes, you can stop the automatic rebooting so you can look at the error more closely. Also see if you can at least get this up and running via the recovery console and examine the event log. There should be some messages indicating what is happening here. J. j e r u v y a t y a h o o d o t c o m

How do you stop it from rebooting? Mine shows an error message for a split second the reboots. If I disable power management in the cmos setup it locks up before it loads windows.