Another dead PSU?

Swi1ch · 12 Jan 2019 at 20:25

Sometime around April last year my PC started randomly losing power. No BSODs or helpful event logs. Eventually the PSU made a load of obvious bad noise and I replaced it.

The new one has been fine up until today, and my PC is randomly dropping power again. No BSODs or event logs, just Kernel Power 63 as before. Changed which wall outlet I had the machine plugged into and that worked for six or seven hours, before dying again. Done the usual; checked cables, reseated cards etc. It's doing exactly what happened previously.

Could some other component in my PC be causing the PSU to fail? Last April was the first time i've had a PSU malfunction in 20+ years. It's seems extremely unlikely to have two fail in the space of nine months.

Possibly, if not probably related, in November my hotswap connection for my harddrive melted, but there wasn't any visible damage anywhere else and the machine worked fine after removing it. I suppose this could have damaged the PSU?

I'm seriously at a loss. I really don't want to be buying another PSU if there's a possibility that something else is causing the PSU to fail.

hughtrimble · 12 Jan 2019 at 20:28

What's the psu and what are the other components you're running?

Swi1ch · 13 Jan 2019 at 01:18

i7 4790k No OC
Corsair H105 AIO
Gigabyte Z97X-UD5H-BK
Kingston HyperX Savage Red 16GB RAM
Crucial MX100 SSD
MSI GeForce GTX 980

First PSU was EVGA SuperNova G2 850W
Second/Current PSU is EVGA 750 GQ

Temps from monitoring software appear fine during power loss (30-40C on both CPU and GPU).

Should also say I've never flashed the BIOS. I considered it before but deemed it too much of a risk with the machine losing power. When I fixed the issue by replacing the PSU I didn't bother as there was no longer a problem and therefore no longer a reason to flash BIOS.

flea.rider · 13 Jan 2019 at 06:07

did evga not replace the old psu ?

Swi1ch · 13 Jan 2019 at 14:28

flea.rider said:
did evga not replace the old psu ?

I never sent it. I had difficulty registering it or something and couldn't really cope with a multi-week wait for sending back, testing etc, so I never bothered.

flea.rider · 13 Jan 2019 at 15:09

Swi1ch said:
I never sent it. I had difficulty registering it or something and couldn't really cope with a multi-week wait for sending back, testing etc, so I never bothered.

multi week ? evga have a uk postage sent one of mine back .. got the upgrade and was back in 5 days .. shame you dint try ..

EsaT · 13 Jan 2019 at 20:33

Only way hardware could stress PSU to wear it down fast would be drawing constantly high power.
And that should be hearable from fan noise and visible also as high temperatures.
PSUs are required to be able to protect themselves from short circuits etc.

Of course having another lemon as PSU wouldn't be entirely impossible.
Though could be also something else.
PSU stays powered on only for as long as motherboard tells PSU to stay on.

One cheap thing to try would be replacing BIOS battery.
Rather unlikely cause, but at least it doesn't cost much to try.