Monitor goes blank.

Hi all, I have a relatively new LG LCD monitor.
Problem is it will frequently go blank, to where there is no image. Not completion black though, there is still a little grayish hue to it and the power light stays on and solid. Its as if I have opened a completely black image and made it full screen, when he monitor is off, it is a darker black.
Anyways, the only way to get the picture back is to unplug the power from the monitor and plug it back in. Restarting the PC will do nothing.

Thanks.