random automatic rebooting

[worldkid]

This problem suddenly started today. I had my Mac Book on and it suddenly turned off, went to black, and automatically rebooted. After less than a minute, it repeated this again and again. There was a "click" heard most of the time when the screen when to black.

I tried running the laptop with only AC, and then only battery. No matter. The problem just keeps repeating itself. Soultions? Ideas?

 

[geoffreak]

Power problems? Maybe a failed CPU (can those even fail )?
Either way, the Apple store is your only bet.