Computer turning itself on

[Churchill]

All good suggestions except that nothing has changed and it has for years worked fine. And it is definitely powering down to full-off state, not just rebooting.

A faulty switch seems it could be possible though you have to push it quite a long way in.

Wake by LAN I considered but wonder why it would only be doing it now. Is it possible this was always on but only recently someone/something has started triggering it... could that be malicious?

Thanks for the ideas.

Have you pissed off anyone at the NSA?

[d000hg]

If your computer is turning itself on, it's probably watching porn when it thinks you aren't looking.

Is that the excuse you use?

[Snarf]

I think I know what's wrong with it. It's not a Mac.

I second this, if it was a Mac the issue would be inverted and it would switch its self off randomly.

[Snarf]

Might not be wake on lAN.. but could be wake on keyboard?

Years ago I worked tech support and we had tonnes of these calls come in turns out our motherboard manufacturer (Matsonic) had changed their defaults to wake on modem - The PCs came on when the phone rang!

[Hobosapien]

Not sure if true but I seem to remember Windows Home Server having a wake for backups option that started up the server, did the backup, and closed it down.

So it could be an OS setting if nothing obvious in the bios, depending how sophisticated the OS version.

Also some mobos have a boot after power interruption option for server use so always on, so could be you turned the power off and back on at the socket or consumer unit causing it to boot up.

Otherwise maybe something faulty and time for a new PC before it sets on fire and burns the house down.

[ChimpMaster]

Turn it off from the plug.

If it comes back on after that, then you know you have a real problem.

[DallasDad]

Turn it off from the plug.

If it comes back on after that, then you know you have a real problem.

+1

Or
I reckon it is
Kids > Router or magic packet > Wol for a giggle
Or
Start with the basics, reset the bios to defaults just in case it been corrupted and is powering the puter up.
Or
Review the event logs
Are the time frames between power down and coming back on again consistent?

[VectraMan]

I had the same thing the other day. My home ClientCo W7 PC that I usually sleep at the end of the day and the weekends kept waking up by itself. Checking the logs showed it was due to the ethernet card. Device Manager properties has options for "allow device to wake up the computer" (on), and "only allow a magic packet to wake computer" (off). Assuming that's the default then it could wake up in response to a connection over the LAN, not just a magic packet.

What has changed is that I've upgraded and rebuilt my W7 desktop. I also put that to sleep and this morning it was on. The event logs showed it woke up at 3am and installed updates! I didn't know Windows Update could do that.

There's a power management option about wake timers, which is presumably what it's using. I have Acronis backup software and that has an option to wake the computer to run a backup.

Remember the good old days when off meant off?

[WTFH]

I had the same thing the other day. My home ClientCo W7 PC that I usually sleep at the end of the day and the weekends

What has changed is that I've upgraded and rebuilt my W7 desktop. I also put that to sleep and this morning it was on.

Remember the good old days when off meant off?

Off does mean Off. Sleep means Standby.

Switch your computer OFF, fully OFF, not "Sleep" when not in use.

[VectraMan]

Off does mean Off. Sleep means Standby.

Switch your computer OFF, fully OFF, not "Sleep" when not in use.

My computer doesn't have an "OFF" option. Just shutdown. After shutdown it can be woken by a magic packet, by pressing the power button (which is a toggle switch, not a switch that has the power going through it) and PCs can still be set up to be switched on by a PS/2 keyboard (not sure if that works for USB).

It's not OFF. According to my power-meter plug thingy my old desktop was still using 1W when "OFF".