Question Pc is randomly shutting down while gaming. Is this my psu?

[salickramnikhil]

My pc has recently started shutting down when under load, at first it was city skylines that it only shut down with (only when I alt tabbed). Now it started when I am stressing my gpu with any game, even league of legends. I bought this power supply second hand, which is why its my first suspect, budget is and was pretty tight so I just want to confirm that it is my psu before dropping a wad of cash on my pc again. When I first got this PSU about a year and a half ago, it performed perfectly fine, without any issues.

[Edit] This problem never happened until I took apart the system to clean it and re - apply thermal paste on my cpu, I have gone back and checked all my connections, temps are perfectly fine. CPU does not pass 65c and my gpu sits at a toasty 85-90c but I do stay in south africa where the ambient temps are high, more often than not at this time of the year the room temp is high 20c to low 30c

The pc shuts down, like the power has been cut, it does not restart. When its idle or just being used for streaming off netflix its perfectly fine.

PC specs:
Gpu: Radeon R9 290x
Psu: Sparta - 750 ? (thats what it says on the label)
Motherboard: Asus H81 - Gamer
Ram: 16gb Corsair vengeance
CPU: I7 4790
HDD: 2tb Segate baracuda
SSD: Samsung 970 evo

 

[Phillip Corcoran]

Could very well be he PSU as it's not a brand I've heard of, nor is it a brand you'll ever see recommended by Tom's. As it stands, you really need to change it, then see what problems, if any, remain.

 

[salickramnikhil]

Could very well be he PSU as it's not a brand I've heard of, nor is it a brand you'll ever see recommended by Tom's. As it stands, you really need to change it, then see what problems, if any, remain.

I dont know what to think anymore, i've been running cinebench and valley benchmark at the same time to stress both cpu and gpu and see what happens if i draw a lot of power and its been completely stable for about 4 hours now. do you still think the power supply is at fault.

[Edit] Dropped my resolution down from 2k down to 1080p just to lower my gpu temps + power draw, do you think that it was hitting its thermal limits, could that cause a pc to switch off?

 

[Phillip Corcoran]

Overheating of either GPU or CPU can indeed cause the PC to suddenly turn itself off --- that's to stop CPU/GPU being permanently damaged. If you need expert/more detailed advice please wait for others to reply as I can't help you any further than what I've already said.