[SOLVED] Curious power weirdness ?

Dec 6, 2021
3
0
10
(Asking in the power supply forum even though i suspect this is more on the motherboard side or motherboard + PS interaction)

My PC would not resume from suspend (S3 suspend to be specific). Suspends fine, but during wakeup it would start booting from scratch as if it was just turned on from complete power off.

This is consistent between windows and linux. I found that if i take my old motherboard + CPU than all works (not even reinstalling any software - same disks, gpu, memory, power supply).

Anyhow at one point i ran out of software tweaks to try and tried to look at +5VSB since this is what is on during the suspend. I stuck a multimeter to the corresponding pin of the motherboard power connector while PC was suspended (other pin just against PC chassis). It shown reasonable value, something like 5.05V or so. So no groundbreaking discoveries.... BUT the resume started working. And when i say started working i've already done like 20-30 in a row it still works, so it is not like some lucky shot and broken again after - it really works consistently (even after i disconnected multimeter from MB connector).

I'm deeply puzzled by this :) I'd think ok maybe some charge??? that i drained while connecting multimeter or something to that effect. Maybe loose contact beween MB/PSU connector? Its been more than a week since resume has been working with 100% reliability. I wonder even theoretically what could this have been? It looks like the measurement has proven the Schrödinger's cat inside the motherboard is alive :)

The setup is Gigabyte gaming X DDR4 motherboard (z690 chipset) / i7-12700kf / Nvidia GPU, power supply is seasonic focus GX650.

Things are working at this time, but what should i try to do / measure this issue happens again? I already tried connecting scope during resume - the +5VSB didn't really sag below spec - was stable.
 
Solution
Update your post to include full system hardware specs and OS information.

Look in Reliability History and Event Viewer for error codes, warnings, or even informational events that correspond with the times of the wakeup /reboots.

Start with Reliability History: much more user friendly and the time line format may readily show when any related errors began and subsequently stopped. When you did the multi-meter voltage tests for example.

A loose connector is a possibility - check all connectors, cards, RAM, and jumpers to ensure that they are all fully and firmly in place.

Look in Update History for any problem updates and re-installs that may have fixed some problem.

Could have been some software bug or file corruption.

Run "sfc...

Ralston18

Titan
Moderator
Update your post to include full system hardware specs and OS information.

Look in Reliability History and Event Viewer for error codes, warnings, or even informational events that correspond with the times of the wakeup /reboots.

Start with Reliability History: much more user friendly and the time line format may readily show when any related errors began and subsequently stopped. When you did the multi-meter voltage tests for example.

A loose connector is a possibility - check all connectors, cards, RAM, and jumpers to ensure that they are all fully and firmly in place.

Look in Update History for any problem updates and re-installs that may have fixed some problem.

Could have been some software bug or file corruption.

Run "sfc /scannow" and "dism"

https://www.lifewire.com/how-to-use-sfc-scannow-to-repair-windows-system-files-262616

How to use DISM command tool to repair Windows 10 image | Windows Central

Just keep checking Reliability History etc. for awhile. If the problem re-occurs hopefully the cause will be apparent.
 
Solution