Desktop PC turning on/off hours after turning it off.

Larry

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Sep 11, 2013
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What would be the most likely reason a desktop PC would constantly turn itself on and off every 3-5 seconds? It turns on long enough to spin the fans and HDDs then turns right back off like it's on a timer. It runs well without issue, but hours after turning it off it starts doing that. Different power supplies and replaced the front power switch...continues doing it. I've went through several power settings and disabled anything I could see like "wake on lan" or anything else, but see nothing. I've unplugged the wireless mouse and keyboard and also pulled the lan cable, it still does it.
 
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GeorgeSoros

My suggestion is you're going to have to do an in depth troubleshoot. Could be a multitude of things. Your PC could be overheating and/or there could be some underlying hardware issues.

I'm curious as to the wattage of the power supplies you used. You might not have an ample supply.
 
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Go into the bios and disable any of the S3 or S states in your CPU settings. There are 'suspend modes' that the CPU will go into. Usually designated S3-S1 states. Make sure those are disabled as well as any 'Power Saving' modes for the CPU. Hit F10 to save and reboot.

This could be the issue, but like wshowers said you might not have the needed power supply. Another option would be that if you have a dedicated GPU to remove it and see if that helps. Make sure your CPU has an IGP though otherwise you won't get any monitor signal.
 
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Go into the bios and disable any of the S3 or S states in your CPU settings. There are 'suspend modes' that the CPU will go into. Usually designated S3-S1 states. Make sure those are disabled as well as any 'Power Saving' modes for the CPU. Hit F10 to save and reboot.

This could be the issue, but like wshowers said you might not have the needed power supply. Another option would be that if you have a dedicated GPU to remove it and see if that helps. Make sure your CPU has an IGP though otherwise you won't get any monitor signal.

It sounds like to me he isn't even getting enough time to get that far. Might be a mobo issue of some kind
 
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It runs fine. This is happening when I'm not using it or attempting to use it. If I intentionally turn it on, then it turns on and boots and runs like normal. This is happening while off early in the morning after using it the previous night.

It has 2010 stuff in it and has enough power for what's in it. It's a Corsair 430W powering a bunch of low end stuff. The video card is so low end it doesn't need a power connector. I'm just trying to keep it running liable enough until this fall.

I will disable that S3 stuff if it isn't already. I just removed a switch from another PC AGAIN and will see if 2 separate switches were the culprit.

NmKetLF.jpg


I haven't seen any caps bulging or leaking. I just hope it's a simple thing to fix.
 
From The command prompt (Administrator):

powercfg -waketimers

powercfg -devicequery wake_armed

Nothing comes up?
 
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^^Also make sure your 24pin motherboard power connector is firmly plugged into the motherboard socket.

I don't think I can remove it again even if I wanted to....

From The command prompt (Administrator):

powercfg -waketimers

powercfg -devicequery wake_armed

Nothing comes up?
OmGIYT2.jpg


I just now disabled that wake timer in the task scheduler and anything that should wake it in the power settings in the past, but not sure if it's the culprit...yet.

PSU not connected all the way or shot?
Any power outages from storms recently?


EDIT: wait that might not be enough power.

It's plenty. HP shipped this pos from the factory with a 250w no name power supply and it ran most of the stuff that's in the picture back in the day. I've swapped it out with a 600w Thermaltake PSU and it still did the same thing.


It's running fine now, but it doesn't do it until the morning, so we'll see.
 
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OmGIYT2.jpg


I just now disabled that wake timer in the task scheduler and anything that should wake it in the power settings in the past, but not sure if it's the culprit...yet.


In the bios you could look for a setting that wakes the computer in case of a loss in power as well.
 
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In the bios you could look for a setting that wakes the computer in case of a loss in power as well.

I've disabled features like that on all of my computers throughout the years whenever installing Windows. It didn't happen this morning, so hopefully the problem is resolved, but I'm sure a new problem will occur shortly.

This issue with this particular PC caused me to run Linux Mint on it for a year or so, because I'd get random BSOD and this random on/off issue.
 
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No, it's more than enough for downloading dirties and giving my laptop a break until I decide whether or not I'm getting a new console or a PC from this decade.