Desktop shutting off seemingly randomly

[Buggrum]

Hi All!

I built my computer last summer and once I'd managed to get it fully operational it had been basically perfect until recently when it started to shut off without warning and seemingly unpredictably. I can always power it back on immediately. I initially thought it might be an overheating problem and it had been a year so I replaced the thermal paste and though I'm not an expert temperatures seem to be within normal ranges.

Here are my specs
Intel Core i7-4790K
Corsair H90
Asus Maximum VII Hero
G.Skill Ripjaw X 2133 MHz DDR3 (16GB)
MSI GTX 980 Gaming 4G
EVGA Supernova 850 watt G2 80 Plus Gold
Samsung 850 EVO (500GB)

Thanks so much!

 

[Dunlop0078]

What temps are you getting? Does it shut off randomly or only when the computer is under load playing a game or something?

 

[Buggrum]

It seems to be random, idle cpu temps are under 40c, when gaming around 54-55c. I've had it turn off once while gaming, but earlier today it turned off when I was just using google docs.