Windows 7: Computer won't wake from Sleep Mode

It does this every once in a while. It happened twice in the past 2 days. I'm not sure if it's something I left open before going into sleep mode or something else.

So the computer's been in sleep mode, usually for at least an hour. I do the usual thing to wake it up, move the mouse. After a simple movement fails, I try again, moving vigorously and clicking all the mouse buttons. I have also tried pressing all the keys on my keyboard.



None of this works and I have to restart the computer. Any idea why this could be happening?

Generally it's the result of a driver power management problem. Most commonly occurring when you have been forced to use a vista driver in place of a proper win 7 driver, as power states have changed a bit between the two.

Okay, so how would this be fixed?

Well the only way I could check anything remotely would be if you had some minidumps to upload so I could look over your driver data.
We could try creating some using this method.
Driver Verifier - Enable and Disable
(Please read all instructions for driver verifier before using as it's possible it will make the machine behave badly and you need to know how to undo it.)