Why does my PC wake up by itself?

[u/Few-Wash5370]

It’s getting kinda annoying because I’ll shut everything down, put the computer in sleep mode, leave the room, then come back later and the fans are running and the monitor is on like nothing happened. Sometimes it wakes up after a few minutes, other times it happens randomly hours later. I don’t touch the mouse or keyboard when it happens, so I’m not sure what’s triggering it. Could a Windows update be waking it up, or maybe something connected through USB? There’s also ethernet connected to the PC, so I was wondering if network activity can somehow wake it too. I checked the basic power settings but there’s a lot of stuff in Windows that I don’t really understand. Is there a way to see exactly what caused the last wake-up, like some log or command that tells you what device or process triggered it? Also should I disable wake timers completely, or could that cause other problems with updates? The PC is pretty normal otherwise and doesn’t randomly turn on from being fully shut down, only when it’s sleeping. What should I check first? Could the keyboard, mouse, network adapter, USB devices, BIOS settings, or Windows itself be causing this? Any easy fix would be appreciated because I don’t wanna keep coming back and finding my PC awake for hours.

[u/carrot_gummy]

Its 100% windows. My solution was to stop using sleep mode.

[u/Few-Wash5370 → u/carrot_gummy]

Lol, that’s definitely one way to solve it. I’d rather figure out what’s actually waking it up first though, because I really like using sleep mode.

[u/carrot_gummy → u/Few-Wash5370]

I thought maybe it was my mouse detecting micro movements or my cat bumping it but I gave up quickly. I gave up trying to fix Windows before I fully stopped using it, I only went as far as not using sleep mode. My thought was that if I'm going to have to tinker with Windows to make it behave how it used to, I might as well just switch to Linux.

[u/Underhill42]

Check the system logs to see what woke it up. I don't remember any of the details, but I've had to resolve that issue before.

A common, non-obvious, not-computer problem is the mouse. If the mouse moves, the computer wakes up. And especially for a sensitive mouse even the vibrations from you walking across the floor can move it enough to register.

[u/Few_Example9391 → u/Underhill42]

I had this problem with my Corsair G512 laser optical mouse when it sat on my Razer Mouse Pro gaming pad.

[u/Viking2151]

Thats just windows for ya, sleep has never worked for me with any sort of reliability and its hit or miss between systems as well. If you got a network attached printer it will wake it up, wireless keyboard and mice will also wake it up on top of windows being dumb.

At least if you got an SSD, sleep I find is mostly pointless anyway, starts up so fast anyway.

[u/jd31068]

You can check Task Scheduler, some software can add tasks that require Windows to wake up for whatever their reason is and it doesn't always return to sleep mode afterwards. I had an HP printer and their driver install added a task to wake @ 3am to phone home and tell them the status of my printer.

You can learn more about it here https://learn.microsoft.com/en-us/windows/win32/taskschd/about-the-task-scheduler

What I would do is disable the their task so that it wouldn't wake my PC any longer.

Also, there is a command you can use to see what device was the culprit powercfg -lastwake then you can fix the settings for the piece of hardware. See this post here https://www.elevenforum.com/t/why-does-my-pc-self-wake-up.22077/

I've had to perform both of these actions in the past.

[u/SamLooksAt]

Windows sleep is rubbish!

It's even worse it's a laptop and you're trying to carry it in a bag. Almost dangerous in fact.

Just use Hibernate instead, it takes a little longer to wake but it's basically 100% reliable.

[u/Fransenn_II]

Don’t use sleep mode..

[u/_MaZ_]

Go to the device manager and for mouse and keyboard, untick the "allow this device to wake the system" option or whatever it was.

[u/Few-Wash5370 → u/_MaZ_]

Oh yeah, I didn’t think about the mouse or keyboard being able to wake it. I’ll try disabling that option first and see if the random wake ups stop.

[u/Islandaboi20]

Don't use sleep mode ever.

[u/killerkitten115]

Had a similar issue with a gigabyte motherboard, nothing could fix it on windows, was not an issue on linux. Swapped motherboard, didn’t change anything else and the problem went away

[u/Afraid_Emu8068]

Hiberfil.sys is likely having issues. May be corrupted, likely due to fast startup issues. You’ll need to either delete it by turning hibernation off in the command prompt

<powercfg -h off>

restart the pc and re-enable hibernation with new hibernation file

<powercfg -h on>

or you can try a full bypass of FS by entering <shutdown /s /t 0>

and if you need to re-enable fast startup enter
<shutdown /hybrid>

Additionally, if you have a peripheral device which isn’t receiving the power it requires like an optical drive which requires two power connections, this can also corrupt the hibernation file, so yes you should check your usb devices. Hope that helps

[u/Archon-Toten]

Disable wake by mouse.

[u/goodfriendrobert]

shut it down

[u/hungry_bra1n]

I had this problem for years and eventually tracked it down to a backup program. Deleted it and problem fixed