Computer shuts down when loading maps in competitive

Roughly 1 out of 15-20 competitive matches I start causes my computer to crash. This only happens when the map is loading right after the phrase “entering map name” is heard.

This doesn’t happen in any other game mode. This doesn’t happen with any other game. Overwatch has been both updated and reinstalled and the drivers have been updated, yet the issue remains.

My hardware is a bit older:

i5 4690k (not overclocked)
AMD r9 280x

Admittedly, the hardware may be a factor or sole cause, but it seems odd that it only ever happens during this specific scenario of loading a map in a competitive game.

Any insight is appreciated.

Did you check the known issues thread stickied in the forum?

Yes, I checked the known issues.

Do a scan and repairs files. That worked for me

And also there are some guides here that show you how to get the best preformance