I have bought a new gtx 970 card and it would have this issue. It would insta shutdown (and reboot) my computer after 5 minutes to 1 hour of game-play (some games did not crash whatsoever). I have already RMA'd the card for the exact same issue and received a new one, but the new card still has the same issue. I've went through everything from clean re-installing my graphic drivers, checking my memory, checking my psu for blown out capacitors, and many other things. My question is: Should i RMA the card again? i'm thinking since the issue is exactly the same as before, and as my previous RMA was successful that means my hardware is faulty. If you are wondering i have stress tested both my CPU and GPU for temperature and they both have performed well with temperatures never going too high. (CPU going to 70 degrees after 1 hour of above 100% performance, GPU never hitting above 80 at 100 percent)
Some basic specs:
PSU: xion 700 watt
Gpu: old : gtx 560 new(card in question): gtx 970 ftw
cpu: i7-2600k 3.4ghz
Memory: 2x4gb ddr3 Ram
Motherboard: Asrock P67 Pro3 se