Computer shuts off randomly ONLY during gaming. Please help

Sojerby08

Honorable
Jul 30, 2013
7
0
10,510
Hey, I've been here before but not really posted. My problem just started recently, my computer started shutting off during gaming. For a few weeks it was working just fine, and I could play hours on hours without any problem. This problem just arose this week, and I can't figure out the reason why. When I'm about 20 minutes into playing a game, lets say Counter Strike GO, it will without warning, shut off completely. I think it has to do something with Windows 10 or my PSU, I could be wrong. Any help would be appreciated, thanks!

My computer specs:
CPU: i5 3570k (Stock Cooler, not overclocked one bit)
GPU: Reference R9 290 (Not overclocked, factory refurbished, pretty much brand new)
MB: Asrock Z77 Extreme 4
RAM: 2X4 GB G-Skill Sniper
PSU: 700W OCZ Modular Plus Rated
Case: Thor V2
Fans: 3 230mm fan, 2 140mm Fan
Optical Drive: Standard DVD+R
SSD: OCZ Trion 100 120GB SSD