JKAsiege

so everytime i want to play any game my computer turns off for no reason.
this only happens when i m on games, because i can be on facebook msn or any other shit all day and nothing will happen
but when i start a game my computer just crash.

like this only happens when is on games i thought it could be my video card, but i got the right drivers and i check for updates but still happens

u know what can be ?

your computer is overheating most likely. some part of it isn't getting enough cooling (either cpu, video card, or the internal temperature as a whole is too high)

it happened to me too a while ago when the a/c in my house broke

Coretemp/Realtemp for CPU temp monitoring
GPU Shark for GPU temp monitoring

The first two are easy to find with googling. The last is a bit more difficult to find, so I'll help.
http://www.geeks3d.com/20111205/gpu-sha ... -released/

You can check cpu-world(.com) to find the recommended temp for your CPU. GPUs are usually rated up in the 90-100C range.

If temps look ok, the next thing to check will be power supply voltages. You could have a damaged PSU that drops voltage out of regulation under load (do you do anything intensive besides games?), causing a system shutdown. A multimeter would be helpful here since software voltage monitoring is somewhat unreliable.