Also, I think my Windows Update may have something to do with it as well. The last couple times it's happened the yellow Windows Update icon popped up in my taskbar. I put off downloading the update because I didn't want to restart my PC. I woke up this morning and my PC was restarted without me doing so.
I seriously doubt it's a heat problem. My temps are moderate.
Is it possible that it's actually something that I can change by going into my Control panel and changing settings?