Question PSU failure - can anyone confirm

Oct 23, 2019
I’m having a weird issue that has been going for a couple weeks and I still haven’t been able to diagnose the problem. Hoping one of the experts on this board can help!

I had an old build I haven’t touched in years (2013?) but was going strong until early this month. I got a black screen suddenly and couldn’t get the computer to restart. I replaced the mobo, CPU, RAM and hard drive, and did a fresh install of Windows. It will turn on now for just long enough to install Windows but spontaneously crashes within 5-10 minutes of low intensity use. I have repeated five times with the same result.

Current build:
MOBO: Gigabyte B450M DS3H (new)
CPU: Ryzen 5 1600 (new)
GPU: XFX Radeon 7800
RAM: 2x Ballastix 4GB DDR4 (new)
PSU: CoolerMaster RS-600W-ACAA-B1

Other info:
Immediately before crashing, the GPU will spin up to max speed and then the monitor will cut out. After cutting out, the computer still seems to be running normally but will then restart in another couple minutes.

I know CoolerMaster has a bad name on this board and I presume 6-year-old CoolerMaster has a worse name. I am leaning towards this being a PSU problem and I’m perfectly happy to shell out for a new PSU if this is the consensus.

The +12V signal appears stable, bounded between 12.312 and 12.386V (software read, don’t have a voltmeter).

I took apart the GPU, cleaned it and replaced the thermal paste - a touch-test makes me confident this is not overheating.

Any help is much appreciated! Thank you.


Could go either way, PSU or graphics card. I'd try the PSU first because you are right, that is not a great model anyhow, plus it is old and should probably be replaced regardless of whether it is the problem or not. Assuming it isn't, and you have to replace the graphics card as well, you wouldn't be wise to use a new card with that old PSU in any case, so even if you have to replace both at least you'll have some insurance against an old PSU potentially be a danger to your new card.

Also, it's not just "this board" that Cooler master has a bad name on. Anywhere you go you'll find most knowledgeable responders will tell you that CM only ever has had a few decent models, and the ones that weren't good were generally pretty bad.


I'd suspect the PSU as well given the low quality of the unit. There are a lot of Cooler Master things I'll use, but with the exception of their high-end stuff like the V series made by SeaSonic, they really cut a lot of corners on the PSUs.