as the title says, whenever i'm playing games on my computer, after anywhere from 5-20 minutes depending on the game, my computer shuts completely off and tries to reboot, but gets stuck on the very first screen. I've always had to do a hard reset just to get it running again. i suspect it might be the CPU, but I've tested multiple tools and the heat doesn't seem to be getting critical, and the CPUs aren't even being run at full force when it crashes. the thing is that it hasn't always done this, and only started relatively recently. I've tried to replace the CPU fan to no avail.