03-29-2014, 06:06 PM
Generally, overheating results in the entire system powering off, not just blacking out, so I don't think that's your problem. My gut reaction is that this is graphics driver related. Make sure you have the latest driver installed for your card and if you do already, I uninstall it (and the Catalyst Control Center software), re download from ATI (AMD now?), restart, and reinstall.