Pc shuts off at random

[Smokeyes]

Pc shuts off randomly while watching twitch or YouTube videos. I restart my pc and after a few seconds of logging back onto the home screen, it just shuts off again. My specs: i7 920, Radeon hd 7850, 3gb ram, vista 64bit. No clue what's going on. Anybody have any ideas?

 

[Reepime]

Sounds like it may be overheating. Let it sit off for a few minutes to cool down (just in case) then when you start it up, check the eventviewer for possible bugcheck logs.

 

[Virax_101]

Pc shuts off randomly while watching twitch or YouTube videos. I restart my pc and after a few seconds of logging back onto the home screen, it just shuts off again. My specs: i7 920, Radeon hd 7850, 3gb ram, vista 64bit. No clue what's going on. Anybody have any ideas?

Are the temps Ok?
Also check if the heatsink is installed properly and has the right amount of thermal compound