Online games freeze my PC

[Klip]

I had issues with (what I thought) was my audio card. I would get weird static noise coming from my speakers (and my pc would freeze, forcing me to turn it off manually) when I played warhammer online and WoW.

I figured it was my audio card (drivers where updated properly.) untill I tried with another audio card and then later I removed a card alltogether and stuck with just using the onboard sound....still the same thing

I honestly don't know what causes these static freezes, it's not an overheating issue as my monitor doesn't power off (I've had overheating problems in another pc, I know what it's like ) I thought it was a problem with the audio card, but I've tried another card and the onboard sound...I just don't know what causes these lock ups...