Demanding games crash, artifact my screen and restart computer.

[Eoghain]

Edit: It's working today, the game runs. Haven't tried furmark. I plugged back in one of my monitors after testing if it crashed with just one yesterday (it did). I don't know if that's in any way relevant.

This started two days ago, I was playing a new game called Playerunkown's Battlegrounds. The game began by just artifacting and crashing, then a few times later the same happened but my computer would restart. While testing it out, I was monitoring my computers temps, everything was stable, my GPU reached a max of 70, but that's still within reason for a AMD card, so nothing wrong there. Next I checked another game, Dayz, and it also crashed, but didn't restart my computer, and the artifacting wasn't as bad. Then I tried it again and nothing, the game ran fine for ten minutes. I reinstalled drivers, changed graphical settings, etc. Nothing has worked. I also tried running furmark, and I'll include a picture of what happened, and sorry for the quality, but it crashed almost immediately. The last thing I did was disable the GPU in device manager, and I ran the culprit game again, and it ran fine. So I'm certain it's the GPU. It's not overclocked and it's running at normal temperatures.

PC specs:
CPU: i7-4790 3.6GHZ Cores 4 Threads 8
GPU: Sapphire Vapor-X R9 280X
RAM: 16GB
Motherboard: b85m-d3h
PSU: CX 750

Sorry for the wall of text by the way.

Here's some pictures I took when testing out different stuff.

This one is the computer restarting.

This is the game crashing and restarting my computer.
https://imagizer.imageshack.us/v2/1136x852q90/923/PFznU4.jpg

This is a different game also crashing how ever it didn't restart my computer.
https://imagizer.imageshack.us/v2/640x480q90/924/rlUPvP.jpg

This is Furmark after being run for 21 seconds.
https://imagizer.imageshack.us/v2/640x480q90/922/vD0bvc.jpg

This is my computer being frozen with weird ambient noises in the background. It didn't restart when it did this.
https://imagizer.imageshack.us/v2/640x480q90/922/dMN54T.jpg

 

[Kronima]

Use windows event viewer to give you a better idea of what is happening when the computer crashes. It'll give you a timestamp of the occurrence and an event ID. Google the event ID number for possible causes and solutions.

 

[Eoghain]

Use windows event viewer to give you a better idea of what is happening when the computer crashes. It'll give you a timestamp of the occurrence and an event ID. Google the event ID number for possible causes and solutions.

Thanks for the response Kronima, I tried that as well, I got 8000400000000002, which doesn't really help me when searching the internet, as it seems to mostly relate to the PSU not being enough to run all the components, and my PSU is pretty okay. I guess it could be defective though.

 

[Kronima]

Power supply sounds like a likely culprit to me, I would go through and double check all psu connections. Then I would try a new good quality psu.

 

[Eoghain]

Okay, major update. I seem to have fixed the problem. Ran furmark, no problems. I reinstalled the GPU, changed the pcie cables powering the card, changed my cable connecting to the monitor from a dvi dual link to a vga cable instead, and so far, it runs games at a higher framerate, it runs everything fine. Only issue is the card is going above previous temperatures, reaching 76 in furmark and 73 in demanding games. How ever, I can live with those temperatures. Any idea which of my changes fixed it? Dodgy cable? Dodgy power cable? Badly installed GPU? Thanks Kronima for the feedback too.