PC restarts after shutdown/sleep/anything (a hardware mystery)

Guys I know that i`m ressurecting this topic, and I do have the same problem, brand new mobo Z370 Aorus Gaming 5 - Gigabyte. I’ve tried evertything, i’ve got off mobo from case, left it alone without anything that could do a short, not pluged on it, except RAM stick, processor and screen, and it still reboot after shutdown 3 secs later.

I’ve sort of been having this problem since my PC was new (about a year ago). Alienware desktop. i7 6700. SSD Windows drive (Win 10) and spinner secondary drive.
It doesn’t do it every time anymore. In fact, after the first few months, the problem mysteriously vanished, and I assumed it was because of a Windows update. But it’s starting to come back, albeit infrequently.

But in my case, I can always tell when it’s about to do a reboot after I’ve given it a “shut down” instruction:

  • The PC will gradually become more and more sluggish, until it takes a full minute just to bring up the shut down menu. If sluggishness occurs for any length of time, I know I will not be able to do a proper shut down.

My first clue is usually when my Amazon streaming video starts to get choppy, and then the audio gets badly out of sync. At that point, if I catch it soon enough, I can sometimes shut the PC down normally. Otherwise, if I don’t catch it soon enough, I have to do a forced shutdown by holding the power button, or else the shutdown command will result in a reboot, and continued sluggishness.

Once I do a forced shutdown, however, rebooting it from cold will always result in a perfectly functioning machine, for several days or weeks even, until it decides to do it again.

It’s aggravating, but at the moment it’s not often enough that I’m terribly worried about it. Just curious as to what might cause this behavior.

Next time it happens, disable audio device in device manager and see if the video still works.

I’m assuming it will still play the video without sound.

For anyone running across this thread and wondering if the problem was solved, a little over five and a half years after I first encountered it, I did some parts upgrading which made the problem go away. Seems to have been the motherboard, most likely.

You are like that one person on Stackoverflow that actually comes back and shares the answer with everyone rather than just “nevermind, I fixed it”. Kudos.

…and doing so after four years? Bravo, sir!