At my workplace, I fully shut down my Windows 8 machine each night before going home. The last couple of mornings, it was turned on when I arrived. Is there some kind of Deep Magic that Windows 8 can use to turn itself on, or is this a clear sign that someone has been turning on my computer before I get to it?
9 Answers
There are a handful of ways a machine can turn itself on from on "off" state. Firstly, modern PCs never truly are off. See ACPI for more information. The computer hardware (not the OS) is checking to see if you press the power button. Other devices can send ACPI signals, such as keyboards with power/sleep buttons. Computer BIOSs can turn a computer on after recovering from a power loss, which is good for machines that need to be on all the time. Wake on LAN (WoL) is another method which can cause a machine to power on.
As for what is causing your machine to wake up, its hard to say. Check your Windows system event logs and see if there are any entries after the time you leave till the time you get in that look pertinent. Your BIOS, might also have some information in its logs.
And the next question, might sound silly, but are you sure you are doing a shutdown and not a sleep?
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1Also, looking through my logs, it looks like my computer really was turning on while I was away. But I was wondering if I had accidentally hit "Sleep" instead of "Shut Down" as well. =P– KevinJul 3, 2013 at 19:43
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2Although to give a more accurate description, the hardware really isn't "checking" to see if you press the power button. That gives the impression that it's actively
polling
, whereas the power button is really just shorting the two pins on your motherboard that start it up. Jul 3, 2013 at 22:20 -
Yes, shorting the pins. But the microprocessor is definitely checking whether the pins are shorted (or rather, whether the relevant pin is pulled down to ground).– MelsJul 4, 2013 at 13:42
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2As a clarification pertinent to this question (and mentioned in a comment on the question): it IS possible for Windows 8 (and other operating systems) to wake the computer, even from the "shut down" state. Often times, this occurs via scheduled tasks. Whether that's what's happening here, or it's one of the many possible other methods Keltari mentioned, I can't say.– NickJul 6, 2013 at 20:26
The only methods a standard PC can "turn itself on" include:
Wake-on-LAN enabled in the BIOS and someone on the network broadcast a WOL packet to it.
Most PCs have a "wake up timer" in the BIOS whereby they can automatically power on at a specific time of day.
Some PCs have a feature where incoming activity on a 56k modem could trigger power on - doubt this applies to your situation.
Some PCs have out of band management hardware such as Intel AMT that can allow administrative personnel to do things remotely like power on the system, even if it is off.
So automatic or unattended power on will involve either someone/something remotely accessing your system or BIOS settings.
EDIT: @Oliver Salzburg has taught me something here - I did not know scheduled tasks could wake a system. Do check that.
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Really. Some times ago (Windows 7 era) my home desktop has a 56k modem card connected to receive fax, and the PC really start itself frequently. Needed to disable PCI wake up... Jul 4, 2013 at 1:51
No, Windows cannot, but BIOS level functions can. Some more sophisticated BIOSes support wake timers (computer wakes up every morning at 6AM), and some peripherals can wake the system as Darius mentioned. Otherwise when Windows is not booted, no, there is nothing it can do to effect its power state.
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4Windows can set those BIOS timers you mention. It is used for scheduled tasks.– Zan LynxJul 3, 2013 at 17:34
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2true, but it can only manipulate them when actually booted. if the OS is asleep or hibernated, it can control the bios functions via ACPI, but when its fully powered down, only the BIOS itself can assert any control. Jul 3, 2013 at 18:08
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2If the operating system wanted to, it could set a timer for every 15 minutes, wake up just a little bit to check on things like reading email for example and then sleep again. Just like a cell phone does.– Zan LynxJul 3, 2013 at 22:39
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agreed. windows systems which are asleep, or hibernated do that all the time, to run scheduled tasks or update checks. But windows cannot boot itself. Jul 4, 2013 at 2:57
I noticed the same behavior on Dell OptiPlex 740 machines that I worked with. Since I had started out with Windows 7, I also had no way to distinguish if it was an OS thing. Someone figured it out how to turn it off here:
http://forums.cnet.com/7723-13974_102-585460/optiplex-740-turns-on-by-itself/
Please access BIOS by pressing F2 key at Dell logo. Navigate to 'Auto Power Time' option listed under 'Power Management' and press Enter. Check if the time is displayed as 5.30 AM.
Navigate to 'Auto Power On' and check if 'Everyday' or 'Weekdays' is selected. Use the left arrow key to highlight 'Off' and press Enter. Press 'Esc' key, select 'Save/Exit' and press Enter.
So that is one answer - that manufacturers have set the BIOS autostart on weekdays as the default. Exactly how widespread this practice is, and when they started doing that, is a curious question.
Go to My computer>Manage>Event Viewer. Here you have history of computer, like when was computer started, which application was started etc etc
If you have authority, check your company security camera, to see if someone is messing up with your computer :-)
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I found this tutorial that discusses using the Even Viewer in Widnows 8: computerperformance.co.uk/win8/windows8-event-viewer.htm– KevinJul 3, 2013 at 16:23
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Yes you can just scroll to the date and see when the computer was started. By switching tabs "system" "Applications" , you can also see which application was started when.– SantoshJul 3, 2013 at 16:37
In my case, my laptop was resuming from sleep because of a scheduled task.
To resolve it, I followed the steps described in this Microsoft Community Forum post:
- Open Task Scheduler by searching for it from Start.
- In the left panel, navigate to:
- Task Scheduler (Local)
- Task Scheduler Library
- Microsoft
- Windows
- TaskScheduler
- In the top center panel, double-click on "Regular Maintenance"
- In the new window entitled "Regular Maintenance Properties (Local Computer)" , select the "Conditions" tab
- Unselect "Wake the computer to run this task"
- Press OK
Keep in mind Management Appliances like the K1000 that may be in place at your work might have a power policy schedule implemented.
http://www.kace.com/products/systems-management-appliance/features/power-management
I am using Windows 8.1. If Windows 8 users can use Alarm app, this tip may also work on their computer. My computer was suddenly turned on by itself when I set my Alarm app to ring at 5 in the morning. I had shut down the computer the night before. Since that time, I have been using this app to automatically turn on my computer at specific time.
Edit: I have just checked Alarms app's faq page. The reason why a PC is turned on automatically is not only because of alarms app, but also because the PC supports InstantGo. I have checked my PC and I guess this is also the reason why my computer is turned on automatically.
Check for your BIOS settings. You will find a solution to restart after SHUT DOWN. If your are HIBERATING or SLEEP then go to power settings in Windows.
powercfg /lastwake
is a good place to start. In my case, it were stupid scheduled tasks that were allowed to wake the machine.