My computer won't go into standby or hibernate

I have a problem that I first noticed yesterday. Whenever I would press the half moon standby button on my keyboard, my computer would go to sleep. I also have a shortcut on my desktop configured to put my computer into hibernate. But now whenever I try to put my pc in sleep or hibernate mode, my monitor goes black for a few seconds but then comes back on at the login screen.

I haven't installed or changed anything other than create a couple logical partitions in the hfs+ filesystem. (still in the process of trying to triple-boot)

Any help would be great, but for now I'm going to bed. Will check back in the morning.

Solution 1:

Go look at your Device Manager, review the Power Management property tab of all your input devices and USB devices. Ensure the Allow this device to wake the computer option is not checked.