Complete system crash/reboot when starting some games

Oct 16, 2018
Hey all, I've been trying everything possible to fix this issue I've had and I've gotten nowhere. I always used Windows 7 but today out of desperation I went and got Windows 10 just to see if it would fix my problems - nope :(

Some time ago I was playing a game of Overwatch online and out of nowhere my screen went black, the sound disappeared and there was nothing else to do than to force shutdown the PC by holding down the power button. No Ctrl-Alt-Delete had any response. I booted up the PC again and it was immediately reproduceable - open up Overwatch, go to a server and within a minute the same would happen. This is especially odd because I have not made any changes to my pc like updating drivers or anything of the sort recently.

Then I tried to update my driver (I have a GTX 670), and still the problem would occur. I attempted to use two different legacy drivers, one from earlier this year and one from 2016, no dice. I now went back to the most recent driver.

I've cleared all my running process, startup programs, services etc. and still no hope to fix the issue. Since then I've been testing this probably more than thirty times using various games. This is the pattern:

Overwatch: Can sit in main menu, after 30seconds to 1 minute of FPS gameplay the computer will crash to black screen, does not reboot automatically
Counter-Strike Source: Can sit in main menu, after 1 minute of FPS gameplay computer crashes to black screen and then reboots by itself.
Counter-Strike: Global Offensive: Can sit in main menu, then immediately upon loading a single player game it crashes to black screen. It finishes the loading bar but the same second it should switch over to the switch team screen it crashes without fail. Reboots automatically
PUBG: Cannot sit in main menu - immediately after loading the main menu it crashes to black screen and does not reboot automatically.
Warcraft 3: Can play, single-player and multiplayer working fine
Quake (1996): Can play
Quake Champions: Can sit in main menu, after 30 seconds of FPS gameplay crashes to black screen and does not reboot automatically
Far Cry 3: Immediately upon loading the main menu it crashes to black screen and reboots automatically.
World of Warcraft, Vanilla (private server): Can play
World of Warcraft, Battle for Azeroth: Can play
Ratz Instagib: Can play
Elder Scrolls V: Skyrim: Can play

So there is quite an erratic pattern as to which games I can play and which games I cannot. One thing I've noticed is that typically older games that are not so graphic intensive run fine (although Skyrim???) while other games, be it multiplayer or singleplayer either let me play for a little bit with fine FPS and then kill my PC, or straight up dabs on me from the main menu.

Has anyone had anything similar to this happen? I've run out of ideas and I'm passing the time frantically cleaning the inside of my rig.