power

[JohnderriLLL]

my friends computer reboots or powers down(i cant remember) after about 3 hrs. what is wrong with it.

[Smoke]

Could be anything with an issue that vague, although I'm betting on the 'overheat' card. Install a temperature monitoring program(Speedfan, MBM) and keep track of the temperature, as well as the point at which it cuts off.

If it's heat, your first option would be checking the fans and CPU cooler for dust.