Why Is My Computer Turning On By Itself?

At the stroke of midnight, every night, my computer automatically turns on. And it STAYS on...for HOURS. One time I checked it 4am, that would be on for 4 hours and it was STILL on! When I turn on the monitor, I am just at the log in screen. I then shut the [bleep] thing off.
This is getting to be a REAL pain. I do not understand why my computer is turning on at that hour, and running for hours, until I shut it off. I have looked at several things in the Control Panel to try and figure out why my computer is doing this. I've checked the Task Scheduler. I do not see anything that is scheduled to turn on at midnight. I've checked my antivirus settings and other applications to see if I have any set to turn on at midnight, for updates or whatever...I cannot find anything. I also have checked Windows Update. I have that scheduled to come on every day at THREE A.M., not midnight. Plus that is greyed out and I couldn't change it even if I wanted to. I don't know what else to look for in the Control Panel or on my computer to determine why my computer is turning on at this hour, and the baffling part...why it stays on for hours until I shut it off. If it was some kind of an update, you would think the computer would shut itself off after it had 'done its scheduled work'. Obviously, SOMETHING on my computer is causing it to turn on at midnight every night and run for hours and I need some ideas on trying to figure out what it is so I can STOP it. Other things or areas I might look at? Any ideas as to what may be causing it to go on, and stay on? Thanks.(I have Vista Ultimate)

 

Have you watched it at midnight to see what it's actually doing? I would expect, once it's completed whatever it is timed to do, that it would stay on. We had a similar issue some years ago with XP MCE turning itself on at 3AM to update its TV guide, and that stayed on too. Caused some real head scratching until we found out what it was and got a fix for it.

 

You may find it's the RTC Alarm Resume under Power Management in your BIOS.
I think if you set the date and time to zero it will turn off (I suspect you might find the time is already set to zero - which is midnight).

 

Thank you for your reply. The wording in my particular BIOS is a bit different than what you are listing, so I am going to list what I have in my BIOS and the settings and then you can advise me as to what to do, change, etc. I don't have a 'Wake on LAN' or a 'Wake on Ring' but I believe I have 'similar' categories. First off, here are the main categories in my particular BIOS, in case you want me to go to a particular category to adjust a setting:

BIOS Main Categories

1. Standard CMOS Features
2. Advanced BIOS Features
3. Advanced Chipset Features
4. Integrated Peripherals
5. Power Management Setup(similar to your 'Power Options')
6. PnP/Pci Configurations
7. Frequency Voltage Control

Categories under 'Power Management Setup', which I think apply to my problem:

1. HDD Power Down-Disabled
2. Suspend Mode-Disabled
3. Video Off Option-Suspend-Off
4. Video Off Method-V/H Sync+Blank
5. Modem Use IRQ-3
6. Soft-Off by PWRBTN-Instant-Off
7. Power On After Power Fail-Off
8. AMD k8 Cool'n'Quiet Control-Auto
9. VGA-On
10.LPT & COM-LPT/COM
11.HDD & FDD-On
12.PCI Master-On
13.Power On By PCI Card-Enabled
14.Modem Ring Resume-Disabled
15.RTC Alarm Resume-Disabled
16.Date(of Month)-0
17.Resume Time(hr-mm-ss)-0 0 0

Please look these settings over and see if they should be as you think they should be. If not, please tell me to change a setting or settings. If I need to go to a different category, please of course tell me the category and what sub-category I should be looking for and what to change it to. Thanks

 

I see your RTC Alarm Resume is Disabled.
You also have Power On by PCI Card enabled. I don't know what this is, and I can't find much about it, but I would try disabling that and see what happens (as well as looking for plodr's suggestions, of course - I see that you have an Advanced tab). It can't do any harm to disable it, and I doubt that you need it enabled. (Do you have a manual for the mother board that tells you what this is?)

 

GCWesq:
That was it! Disabling Power On By PCI Card got the computer from starting by itself at midnight. At least one day it hasn't, but I am thinking this problem is solved. Question still looms in my mind. WHY did my computer suddenly begin starting by itself?? This setting has always been enabled, yet this is just a recent occurrence. Strange. Anyway, I am happy that problem is solved, but I have a new problem(don't they ever end, lol???). It has to do with my System Restore. I am wondering what forum to put that post in, which would be most appropriate. Moderator if you could tell me, I'd appreciate it. Otherwise, I will post it in this forum, and you of course may move it to the 'proper' forum, if necessary. Thanks for all your help!

 

System restore is software-based. Post in the software forum.

Glad you're up and running.

 

Excellent.
Thanks for update.
I have no idea why these things suddenly raise their ugly heads. It may just have been a startup glitch that changed that setting (are you sure that setting was always enabled?)??? Or maybe you updated something that decided it wanted to change that as well. A new bit of hardware, perhaps? Leprechauns???

I'll be moderator for a day (well... for a minute...) It sounds like a software problem, so a post here will be fine.

 

If all of that geeky stuff fails, you could plug all devices related to the PC on a single power strip with a switch and turn off the switch after shutting down for the night.