Pc Crashes when under load

Loyal2017

Commendable
Jan 12, 2017
7
0
1,510
Currently i have a msi gtx 970 with an amd FX8350. Regularly my pc will crash when under some load like running bf4, rainbow 6 siege or gta v. I would be casually playing a game and suddenly the pc would go to a black screen, all the fans would stop for a second and windows would reboot itself. The games seem to be running fine with no lack of fps or lag spikes too. Does anybody know what part/parts of my pc is failing and/or have any solutions?
PC SPECS------
-Amd FX 8350 (water cooled with a corsair H55)
-MSI GTX 970 4gb (note- my temps can sometimes get high. the highest i've seen it at is ~70 degrees but im sure its been higher)
-8GB DDR3 2400Mhz dual channel corsair vengeance ram
-Gigabyte GA-78LMT-USB3(socket AM3+) motherboard
-EVGA 550watt Fully modular power supply
 

Bosch14

Distinguished
Feb 25, 2015
39
1
18,615
sounds like a PSU problem to me but try this first and post back http://outervision.com/power-supply-calculator.
Also when you try and boot you PC back up does it do it right away or does it take a while to be able to boot up again.
 

Loyal2017

Commendable
Jan 12, 2017
7
0
1,510


Ok i put all my parts into the calculator and got an ideal wattage of 449 watts ( https://gyazo.com/639e122b5688dfb22aab67e248b7bde5 ). also i dont boot my pc up its like windows is restarting itself. its like im pulling out the plug so i get a black screen straight away then windows automatically boots straight away within a couple of seconds.
 

Loyal2017

Commendable
Jan 12, 2017
7
0
1,510


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