My PC first had Vista installed and I had no problem playing games such as WoW and such. Then I moved to Ubuntu, and it started to turn off after ~2-5 mins after starting some heavy game. The PC couldn't turn on, only if I took out the battery (it's a laptop). Today, I installed Windows 7, and after turning on WoW and playing for 2 mins, it turned off again. I tried playing without a battery, but still with no result.
If anyone could please help me, I am all ears.