I have a Dell computer that is basically a back up computer and so it sits idle a lot. Used it a few weeks ago, and it was fine. Turned it on this morning and the screen is black. Pressing one of the small lights at the bottom of the monitor brings up the message, You are in Power save. Press any button or move your mouse to continue. Well, I did that and nothing happens. Have checked all wires. Everything seems fine. Please how do I get out of power save and bring the screen back to life?????