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Dreaded Critical Error (Kernel Power 41), found out voltage drop on PCI-E. Does it indicate PSU or could it be MoBo/CPU?

qwwoop

Commendable
Jan 31, 2017
5
0
1,510
Hello,

I've spent about a week chasing dead-ends trying to solve the issue of my PC randomly rebooting. Most of this time was spent trying to find software fixes, as it only happened rarely and once booted.

The PSU was bought second hand as I was strapped for cash, and worked for ~3 days, after which it started to randomly reboot, first under load, then at all times. It seemed the PSU was at fault, so I got it replaced for another. This seemed to solve the issue - for another 3 or so days, when the issue reappeared.

Finally I've measured the voltage of PCI-E when PC was on, and noticed that every time the voltage drops to 0 for ~2s, then back to 12V. The question is - is it the PSU's fault, or could it be the motherboard as well?

Here's the vid of it in action: https://www.youtube.com/watch?v=xZucsngORz4
 
Oh, and I don't have an easy access to another PSU/Motherboard. If I had, there would be no question.

And for what it's worth, there is no voltage drop when you reset the computer with a button.
 
Yep, the LEDs are my primary indicator when the power goes off. Tried two diff. SATA cables, but it also happens on Linux Live USB or once even in BIOS without any HDD attached.

When I short pins 15+16 on 24pin cable so the PSU turns on without connecting to Mobo, it doesn't reset. Not sure what to make of it.
 
I've checked it all. As I've said, everything works just fine unless it's actually connected to PC and running.

I know that I'm unlikely to get any conclusive answer and there's probably no avoiding getting another new PSU to really know, but hey, who knows?
 
when you check the outlet do you have a constant 110 volt readings when you strart and run pc if yes then there is something that short psu in system check all parts by usindg minimal parts at start up and adding other even the case fan .
 
230v, Europe here, but yes. There's literally only mobo, cpu, cpu cooler, 1 ram stick and hdd connected (happened even without the HDD). I mean, I'm grateful for your responses, but I (mostly) know what I'm doing.

What I'm asking for is that, based on the video of the voltage drop, whether one can tell if it's def. the PSU or is it possible (not certain, but _possible_) that the mobo is the one causing trouble.
 
that ram could you check her out or use another in the system if it does the same either cpu have bent pins or board going out the other thing you stand off post are well fix in the case and nothing from board to them made short with the case .