• Happy holidays, folks! Thanks to each and every one of you for being part of the Tom's Hardware community!

[SOLVED] Faulty PSU?

alexswede

Reputable
Apr 26, 2017
126
5
4,585
For the past 5 days or so my PC has been randomly turning off, then after about 2-3 seconds it turns back on again. I cant seem to find any pattern to when it happens, sometimes its when i enter bios, sometimes its after 4 hours, sometimes after 3 minutes. I went into the event viewer and saw that im getting Critical Kernal Power 41 events. I looked online and tested multiple different "fixes" including running CHKDSK and SFC (doubted this would work but tried it anyways), updated my bios and drivers, aswell as picking apart my pc and re seating most of the hardware and cables. Yet as soon as i turned it on again, it restarted after about 10 minutes.

Specs:
AMD Ryzen 7 3700X
CoolerMaster ML360R AIO
ASUS ROG STRIX X570 GAMING-F
TRIDENT Z NEO 32GB 3600MHz CL16
ASUS TUF 3080 OC
7 Total case fans (three in front with radiator, three on top for exhaust, 1 in back for exhaust)
Samsung 970 EVO M.2 1 TB
Samsung 860 EVO SSD 1 TB
Corsair RMx (2018) 750W PSU

Could it be a faulty PSU? i know its extremely hard as a normal PC owner to REALLY test a PSU, but this problem has only been happening recently, so im really not sure whats going on, any help is really appreciated!
Event Viewer: View: https://imgur.com/eYvAAzf
 
Solution
Sometimes a PSU fan won't spin unless it's warm enough / under enough of a load.

From: https://www.corsair.com/corsairmedia/sys_master/productcontent/RMx_2018_Manual.pdf

Zero RPM mode
Zero RPM mode allows the fan to remain off during low to medium loads. This technology uses various temperatures from inside the PSU and the power output level to determine when active cooling is needed for the PSU. When you’re pushing it hard the fan will turn itself on to ensure that it gets the cooling it needs without any extra noise. For the specific fan profile of your unit please refer to the specifications section of that PSU.

So the fan isn't spinning at all? Can you manually turn it with a toothpick / zip tie? (anything non...
3080's can have some high wattage spikes causing some PSU's to trip a protection circuit but it seems this is happening when you are doing normal things other than gaming. Is that correct? I would still point the finger at the PSU. Not that 750w isn't enough but maybe something faulty. Make a bootable USB and run memtest for an hour just to rule out a really bad stick of RAM. https://www.memtest86.com/download.htm
 
Sometimes a PSU fan won't spin unless it's warm enough / under enough of a load.

From: https://www.corsair.com/corsairmedia/sys_master/productcontent/RMx_2018_Manual.pdf

Zero RPM mode
Zero RPM mode allows the fan to remain off during low to medium loads. This technology uses various temperatures from inside the PSU and the power output level to determine when active cooling is needed for the PSU. When you’re pushing it hard the fan will turn itself on to ensure that it gets the cooling it needs without any extra noise. For the specific fan profile of your unit please refer to the specifications section of that PSU.

So the fan isn't spinning at all? Can you manually turn it with a toothpick / zip tie? (anything non metallic) See if it's obstructed?

I don't know if that fan will 'spin' a little on power up (like a self test) or only when it's warm or under load.

Last thing, can you watch the fan on startup and see if it stutters a little? (like it's trying to start?)
 
Solution