I have been having random lock ups during game play for about 3 months, which a hard reboot fixes. Typically, it happens about twice a week on about 30 -40 hours of game play. I upgraded my gpu today and it wouldn't start back up (went from 560 ti to 1060, which is less draw). The PS fan would start to spin then stop and one case fan would spin and stop, briefly. When it was freezing all temps were normal and nothing seemed a miss. Did the normal checks, disconnect gpu, visual of MB, ram (one at time), ect. Got to the point i was sure it was the PSU and replaced it and it booted right away. Haven't had a chance to tinker with with and am one not to mess with something that works, but could a bad PSU just stop working like this? Seems like an MB issue, more than anything. Any suggestions?