This doesn't tell us if your PC is working or not. Just that the monitor has no signal so the monitor decided to go to sleep.
Double check your work, especially the monitor to PC connections.
Bob
I own a Dell computer.
I recently moved. When I arrived at my new home and hooked up my computer, here's what happened:
computer started
screen came on and had the message "power save mode"
screen went off and no matter if I hit the mouse or keyboard, the screen does not come back on...unless I hit one of the buttons on the screen. When I hit this button, I see a message saying it is searching and then I get the message that it is in power save mode and the screen goes blank again.
I am a novice/ignorant woman when dealing with computers and have no idea how to trouble shoot this. Can anyone help?!?!?! Thanks so much.

Chowhound
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