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My Win 7 RC will not stay "Asleep". After about two minutes it wakes up. It won't go to sleep after the TV show is recorded and finished either. So, my computer is on most of the time. What can I do?

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You could also open up a CMD window with Administrator privileges (Accessories/Command Prompt - right click: Run as Administrator).

Once it's open, type:

powercfg -lastwake

That should tell you the last thing that caused your PC to wake up...

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+1 for answering the specific question as asked – AdamV Nov 16 '09 at 10:22

The event that wakes up your computer is recorded on the Events Log. So you may want to search from there.

But from your description, a few ideas:

  • The network card can wake your computer if there is incoming connections as per NDIS Power Management normal rules. This can be configurable.

  • Ping events can wake up a computer, no matter NDIS settings. If your machine is on a home network and it's is pinged from another computer in the private network, it will wake up.

  • Similarly, Network shares can wake up your computer. Again, only relevant if you are on a private home network.

  • Software can wake up your computer. Applications running in the taskbar are likely candidates, while Anti-virus or personal firewalls being prime candidates, as well as any other application which does automatic updates.

  • Wireless mice has been known to interfere with sleep mode. Lower quality equipment (either the mouse or the motherboard usb port) can introduce "vibrations" in the wireless link that ends up simulating movement (does your mouse tend to sometimes do a jerking motion?).

  • Last, but not least, the usual suspects: virus or rootkits.

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Anything suspicious in the Device Manager? – Guy Thomas Nov 15 '09 at 9:50

Run in command line "powercfg -energy" (no quotes). That'll give a list of loads of power related items, identifying which have an effect on energy comsumption. See if there's anything weird in there.

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+1 because this is today's "new thing I learned about". And it coincidentally helped me identify a problem with svchost sucking up processor time with a driver that is a) badly broken b) not needed for my setup (I don't use my smartcard reader). Performance just took a leap upwards! – AdamV Nov 16 '09 at 10:24

You mention something about TV recording. If you have software that is set up to record programmes on a timer basis, then I would not be at all surprised to find that waking up the computer to ensure it does not miss a time slot.

What you can do in more general terms is ensure that even if it is on, it is using minimum power necessary - turn screen off, spin disks down etc. Is this a laptop or 'desktop' PC

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