The power supply is about 4 months old. I checked it out with a power supply tester (both 12v rails) and they check out as clean/functioning properly with no drops or spikes (done under a simulated load as well) so I'm fairly sure it's not a power supply issue. The power supply is a 750w Gold so of (should be!) good quality. The only time I get this rebooting problem is when running FFXIV. Other games/software run as expected without issues. I did connect another PS (1000w) which did not make any difference ...I had the same thought (lol) The game seems to be running better after changing some settings in NCP, but still crashes and reboots the comp after a bit (randomly) anywhere from a few minutes to 30-1hr. Puzzled now... Haven't seen any recent posts in Nvidia forums about this...only old ones. That's where I got the settings to change in the control panel. This seems to be an issue that has cropped up before but has never been sufficently explained or dealt with by either Nvidia...or Square Enix. Not to sure what to do now.....