W7 restarts instead of shutting down

[NINaudio]

Hey, I have this issue where whenever I try to shutdown win7 it ends up restarting. A list of what I've checked and tried so far:

I've doublechecked my wake-on-lan settings in the bios and device manager and they are disabled.

Do a diagnostic startup from msconfig and the issue still happens.

Shutdown from welceom screen before logging in and the issue still happens.

Run ad-aware and malware bytes, issue still here.

Any other ideas? I was thinking a stuck power switch, but that seems unlikely as I think it would make my machine just keep turning on and off.

Thanks!

 

[NINaudio]

Is it possible that this is a PSU issue?

When I turned my pc on tonight it appeared to power cycle 5 or 6 times before it started to load the bios screen. Then it froze and I noticed that the fan on my psu was very dim. A click of the reset button and it started up normally.

 

[Steltek]

If you aren't running on a UPS which has gone bad or a bad electrical circuit, it definitely sounds like a power supply issue. Were it me, I'd swap it out first before doing any other type of troubleshooting.

 

[NINaudio]

Swapped out the PSU amd voila, windows shuts down and starts up normally. Was lucky enough to still have the PSU from before this one. =)