[SOLVED] PC not staying shutdown - possible power supply issue?

Nov 1, 2020
6
0
20
1
Hi everyone, I've started having an issue where my PC simply will not stay shut down and was hoping someone might have some advice.

The problem and background:
When I shut down my computer or put it to sleep, it does not remain in these states and will immediately boot back up. The effect is exactly as if someone was pressing the front panel power button immediately whenever the computer turns off. It's maybe noteworthy that the PC does manage to shut down properly - everything goes dark, fans stop running, no noise, etc., it just always starts back up within ~5 seconds.

This problem only started a few days ago, right after I had moved my whole setup to replace my desk. I may have accidentally swapped the power cables for my PC and my monitor during this process, which is the only thing that changed regarding my PC.

Hardware specs:
I built this computer in 2013 or so, most of these components are from then:

CPU: Intel Core i5-3470
Motherboard: MSI Z77A-G45
Memory: Crucial Ballistix Sport 1x8GB DDR3-1600
Storage:
  • 2TB Seagate HDD (Windows 7 boot drive)
  • 1TB Crucial SSD (Windows 10 boot drive, recent addition, default OS)
  • 2x 120GB Intel SSDs
GPU: MSI GTX 760 OC
Power Supply: Corsair CX500

Things I've tried:
  • All of the standard windows 10 fixes (registry edits, Fast Startup, wake on network access, etc.)
  • Reset CMOS (twice)
  • Disconnecting front panel power button from motherboard to rule out faulty front panel connector
  • Boot into Windows 7 and shutdown to rule out Windows 10 issues
At this point, I feel like I've run out of things to try, and all signs point to it being a hardware issue. Since the only thing that changed was me accidentally swapping power cables, I'm guessing it's a power supply issue, although I also wouldn't be surprised if it's a motherboard issue now (maybe the cable change fried it in some way?). My next steps were going to be replacing the PSU, and if that doesn't fix the problem, then replacing the motherboard entirely.

Any advice on other things that I could try to identify the issue or ways of fixing it would be much appreciated. Thanks for any help!
 
Nov 1, 2020
6
0
20
1
Not a problem. Hope your problem goes away.
So last week, before ordering a new PSU, I decided to just open up my case and 'reset' things a bit - reseated my RAM and GPU, disconnected and reconnected the power to the motherboard and hard drives, reset CMOS once more, and lo and behold, the problem disappeared! The computer has been stable since then, so I feel comfortable saying the problem is gone now. Not really sure what it was in the end, my leading theory is that when I was moving the PC, the RAM might've wobbled into a weird position and the reseating fixed it, but I guess I'll never know for sure. Cheers and thanks again for all the suggestions!
 

xenthia

Distinguished
Sep 20, 2012
174
16
18,595
4
Hi everyone, I've started having an issue where my PC simply will not stay shut down and was hoping someone might have some advice.

The problem and background:
When I shut down my computer or put it to sleep, it does not remain in these states and will immediately boot back up. The effect is exactly as if someone was pressing the front panel power button immediately whenever the computer turns off. It's maybe noteworthy that the PC does manage to shut down properly - everything goes dark, fans stop running, no noise, etc., it just always starts back up within ~5 seconds.

This problem only started a few days ago, right after I had moved my whole setup to replace my desk. I may have accidentally swapped the power cables for my PC and my monitor during this process, which is the only thing that changed regarding my PC.

Hardware specs:
I built this computer in 2013 or so, most of these components are from then:

CPU: Intel Core i5-3470
Motherboard: MSI Z77A-G45
Memory: Crucial Ballistix Sport 1x8GB DDR3-1600
Storage:
  • 2TB Seagate HDD (Windows 7 boot drive)
  • 1TB Crucial SSD (Windows 10 boot drive, recent addition, default OS)
  • 2x 120GB Intel SSDs
GPU: MSI GTX 760 OC
Power Supply: Corsair CX500

Things I've tried:
  • All of the standard windows 10 fixes (registry edits, Fast Startup, wake on network access, etc.)
  • Reset CMOS (twice)
  • Disconnecting front panel power button from motherboard to rule out faulty front panel connector
  • Boot into Windows 7 and shutdown to rule out Windows 10 issues
At this point, I feel like I've run out of things to try, and all signs point to it being a hardware issue. Since the only thing that changed was me accidentally swapping power cables, I'm guessing it's a power supply issue, although I also wouldn't be surprised if it's a motherboard issue now (maybe the cable change fried it in some way?). My next steps were going to be replacing the PSU, and if that doesn't fix the problem, then replacing the motherboard entirely.

Any advice on other things that I could try to identify the issue or ways of fixing it would be much appreciated. Thanks for any help!
While this might not be the original cause, it is possible that the BIOS battery has lost its power and or after the move the BIOS settings were reseted.

Motherboards have a section related to power settings and management. Have a look there and check if the setting is as such to keep the system off for when the power returns. and also check the standby settings as well as checking to see if the mouse events or keyboard events or any other clocks or events to turn on the system are off.
 
Nov 1, 2020
6
0
20
1
While this might not be the original cause, it is possible that the BIOS battery has lost its power and or after the move the BIOS settings were reseted.

Motherboards have a section related to power settings and management. Have a look there and check if the setting is as such to keep the system off for when the power returns. and also check the standby settings as well as checking to see if the mouse events or keyboard events or any other clocks or events to turn on the system are off.
Thanks, you're right that the BIOS settings did reset after the move, but they have reset in the past for various reasons as well and I've never had problems like this. I looked around the BIOS and the only settings I see in the Power Management section are EuP 2013 (which is disabled) and the "wake on mouse/keyboard/etc" events, which are all off.

Also kind of interesting is that suddenly my BIOS is taking a while to load on startup. Previously this was instant, but now it's taking a solid 5-10 seconds to show the BIOS screen after initially powering on. I wouldn't be surprised if this is related to the boot issue (perhaps the power supply isn't providing power quickly enough or the motherboard battery is misbehaving?). Maybe a BIOS update and/or replacing the motherboard battery is in order before replacing the PSU or motherboard itself?
 
In the bios, you may have some wake on lan activity set on.
I think windows may set this so they can push out updates while you sleep.

Do you have cats?
They will walk over your keyboard like mine and wake up the pc.
Change to not let the keyboard wake, only the power button.
 
Nov 1, 2020
6
0
20
1
In the bios, you may have some wake on lan activity set on.
I think windows may set this so they can push out updates while you sleep.

Do you have cats?
They will walk over your keyboard like mine and wake up the pc.
Change to not let the keyboard wake, only the power button.
All of the "wake on *" fields are disabled in the BIOS. And heh, no I don't have cats or anything causing this - I can hit the shutdown button, take my hands away from my desk entirely, and the PC will turn back on no matter what.
 

xenthia

Distinguished
Sep 20, 2012
174
16
18,595
4
Thanks, you're right that the BIOS settings did reset after the move, but they have reset in the past for various reasons as well and I've never had problems like this. I looked around the BIOS and the only settings I see in the Power Management section are EuP 2013 (which is disabled) and the "wake on mouse/keyboard/etc" events, which are all off.

Also kind of interesting is that suddenly my BIOS is taking a while to load on startup. Previously this was instant, but now it's taking a solid 5-10 seconds to show the BIOS screen after initially powering on. I wouldn't be surprised if this is related to the boot issue (perhaps the power supply isn't providing power quickly enough or the motherboard battery is misbehaving?). Maybe a BIOS update and/or replacing the motherboard battery is in order before replacing the PSU or motherboard itself?
This to me sounds a tiny bit of a fault BIOS firmware now, or a sign of BIOS malware activity of some sort.

Here is what you can try:

Go to your motherboards website look for a section that lets you download firmware and drivers. Head on to the BIOS section.

In here, it is the standard to have multiple version of BIOS available. Fr example I have looked on there for you and here is the most recent BIOS https://download.msi.com/bos_exe/mb/7752v2C.zip (look for that your self don't trust ANY links a stranger gives you ;)) then download that. Also download like one or two updates before that. like 2A in your case https://download.msi.com/bos_exe/mb/7752v2A.zip.

Then put the most recent one (2C) and (2A) on a flash usb and update your bios firmware but in this order.


Shutdown the system. Remove the power cable. disconnect any and all hard disks, or USB flash sticks or so, but the one containing the BIOS firmware. update the BIOS with 2C first, like flash it, to replace the firmware COMPLETELY. let it restart perhaps a couple of times,

Then update the BIOS with 2A (the older one) and again wait for it to perhaps restart a couple of times. Then Update BIOS firmware again with 2C (the most recent one).

This is to make sure that perhaps some APT (Advanced persistent threat ) related BIOS malware or a faulty BIOS is off your system. But don't expect this to be of much help against sAPTs or super Advanced persistent threats sort of.

After that, if your BIOS has a password access or any other security measures activate those to prevent an unknown or unwanted BIOS access and update.

This should take care of most BIOS problems.
If not it is safe to assume this is a much deeper hardware problem with the BIOS chip or the motherboard.
Hope this helps. cheers . :beercheers:
 
Nov 1, 2020
6
0
20
1
This to me sounds a tiny bit of a fault BIOS firmware now, or a sign of BIOS malware activity of some sort.

Here is what you can try:

Go to your motherboards website look for a section that lets you download firmware and drivers. Head on to the BIOS section.

In here, it is the standard to have multiple version of BIOS available. Fr example I have looked on there for you and here is the most recent BIOS https://download.msi.com/bos_exe/mb/7752v2C.zip (look for that your self don't trust ANY links a stranger gives you ;)) then download that. Also download like one or two updates before that. like 2A in your case https://download.msi.com/bos_exe/mb/7752v2A.zip.

Then put the most recent one (2C) and (2A) on a flash usb and update your bios firmware but in this order.


Shutdown the system. Remove the power cable. disconnect any and all hard disks, or USB flash sticks or so, but the one containing the BIOS firmware. update the BIOS with 2C first, like flash it, to replace the firmware COMPLETELY. let it restart perhaps a couple of times,

Then update the BIOS with 2A (the older one) and again wait for it to perhaps restart a couple of times. Then Update BIOS firmware again with 2C (the most recent one).

This is to make sure that perhaps some APT (Advanced persistent threat ) related BIOS malware or a faulty BIOS is off your system. But don't expect this to be of much help against sAPTs or super Advanced persistent threats sort of.

After that, if your BIOS has a password access or any other security measures activate those to prevent an unknown or unwanted BIOS access and update.

This should take care of most BIOS problems.
If not it is safe to assume this is a much deeper hardware problem with the BIOS chip or the motherboard.
Hope this helps. cheers . :beercheers:
I was planning to try this today, but when I went to turn on my PC, it flashed some lights, tried to load up for a bit, and then powered off. Trying again after a few minutes worked and seems to be stable (I'm typing this response from the PC in question), but this really seems like a dying PSU to me now. Do you still think I should bother with BIOS/motherboard investigation or just go ahead and replace the PSU at this point?
 

xenthia

Distinguished
Sep 20, 2012
174
16
18,595
4
I was planning to try this today, but when I went to turn on my PC, it flashed some lights, tried to load up for a bit, and then powered off. Trying again after a few minutes worked and seems to be stable (I'm typing this response from the PC in question), but this really seems like a dying PSU to me now. Do you still think I should bother with BIOS/motherboard investigation or just go ahead and replace the PSU at this point?
Well the original issue was not that the PC would not turn on, it was that if you turn it off it would turn back on.
But if during your diagnosis you have come to the conclusion that the PSU might be at fault why not? Try replacing it and check if that works. This would be an exceptional PSU though with probably some form of extra kit to send a signal to turn the computer back on.
But again I am not there in your situation so if you think this is a problem caused by the PSU, replace and see if the computer stays off.
 
Nov 1, 2020
6
0
20
1
Well the original issue was not that the PC would not turn on, it was that if you turn it off it would turn back on.
But if during your diagnosis you have come to the conclusion that the PSU might be at fault why not? Try replacing it and check if that works. This would be an exceptional PSU though with probably some form of extra kit to send a signal to turn the computer back on.
But again I am not there in your situation so if you think this is a problem caused by the PSU, replace and see if the computer stays off.
Yeah that makes sense - I'm not entirely convinced that the original problem was caused by the PSU and I would like to try a BIOS upgrade as you mentioned, but I think there is some PSU issue right now and I don't want to end up in a state where the PSU fails while the BIOS is upgrading. I'll replace my PSU and post again with any updates afterwards. Thanks for all your help so far!
 

xenthia

Distinguished
Sep 20, 2012
174
16
18,595
4
Yeah that makes sense - I'm not entirely convinced that the original problem was caused by the PSU and I would like to try a BIOS upgrade as you mentioned, but I think there is some PSU issue right now and I don't want to end up in a state where the PSU fails while the BIOS is upgrading. I'll replace my PSU and post again with any updates afterwards. Thanks for all your help so far!
Not a problem. Hope your problem goes away.
 
Nov 1, 2020
6
0
20
1
Not a problem. Hope your problem goes away.
So last week, before ordering a new PSU, I decided to just open up my case and 'reset' things a bit - reseated my RAM and GPU, disconnected and reconnected the power to the motherboard and hard drives, reset CMOS once more, and lo and behold, the problem disappeared! The computer has been stable since then, so I feel comfortable saying the problem is gone now. Not really sure what it was in the end, my leading theory is that when I was moving the PC, the RAM might've wobbled into a weird position and the reseating fixed it, but I guess I'll never know for sure. Cheers and thanks again for all the suggestions!
 

xenthia

Distinguished
Sep 20, 2012
174
16
18,595
4
So last week, before ordering a new PSU, I decided to just open up my case and 'reset' things a bit - reseated my RAM and GPU, disconnected and reconnected the power to the motherboard and hard drives, reset CMOS once more, and lo and behold, the problem disappeared! The computer has been stable since then, so I feel comfortable saying the problem is gone now. Not really sure what it was in the end, my leading theory is that when I was moving the PC, the RAM might've wobbled into a weird position and the reseating fixed it, but I guess I'll never know for sure. Cheers and thanks again for all the suggestions!
Glad to be of any help and it seems like you solved the problem by just reseating the components.
Feel free to pick an answer as the best answer and mark this thread as solved so if any one finds themselves in a similar situation can try and fix their problems. Cheers.
 

ASK THE COMMUNITY