In April I bought mw3 for my pc, it worked great, until a month later (few weeks ago), it shuts down my computer now. I start it up, and everything freezes and then my computer just shuts down. I've done everything, un-installed/re-installed Steam AND Mw3, defraged the mw3 cache, everything.. And it still shuts down my computer.. I've updated my BIOS and it still doesn't work. Can anybody please help? I miss playing mw3