Computer Starting Up Immediately After Sleep or Hibernate

When I sleep or hibernate my computer, within 10 seconds of it turning off, it turns back on again by itself. When it turns back on, there is no output on my monitor. I used remote desktop from another computer to see whether it was just the video that wasn't being reposted, but when I tried to connect, it couldn't find the computer. None of the keys work on my keyboard, including the sleep and power buttons.

I have an ASUS P5LD2 Deluxe motherboard, and an Intel 3.0 GHz processor. I'm also running the x64 version of Windows 7.

Any ideas how to stop it starting up autonomously ?

It is probably the Wake on LAN feature kicking in, so it would be worth trying to disable it. To do so, open the device manager and find your network card(s). Right click on it and go to properties, then click on the "power management" tab. You should have a box called "allow this device to wake the computer", untick it and click OK.

See if it works once you've done that

I did what you said, but when I went into the properties, the box was greyed out, although it wasn't ticked. I've also checked my BIOS, and it doesn't have a Wake on LAN feature.

Can you see anything in Event Viewer that happens around the time your PC wakes up? You might have some software (AV, anti Spyware scanner etc... that is waking your PC up).

Also, do you have anything set to wake your PC up in the Power Options menu (in Control Panel).

edit: Is there an "advanced" tab in the device manager properties for your network adapter? Sometimes there is a dropdown list with an extra WOL property in there which might be worth disabling too.

I have USB wake timers enabled in the control panel, but this is because I have a USB TV card, that wakes the computer when it's about to record something.

In the Event Viewer, the only processes that run when the computer is about to turn off are:

Successfully scheduled SPPSVC for re-start at 2009-06-17T23:59:52Z. Reason: Beta Keys.
Security SPP: The Software Protection service has stopped.

How do I find out if they can start the computer up?

Cheers.

I'm not sure on that one, I'll do a bit of digging and see if I can find anything.

The easiest way to check is to briefly disable your LAN adapters in the device manager and put the PC into hibernate. If you have a Logitech G7 mouse, remove the battery.