The screen on my I8600 randomly turns off and I need to restart the computer in order for the screen to turn back on. This started happening not too long ago, roughly a 2 weeks ago. I mentioned it to Dell when I sent my notebook in for repair but they only replaced the motherboard and the problem still persist. I thought it was a driver issue but it just happened in BIOS not to long ago so I don't know anymore.  I've already had several occasions where the screen would go black at the wrong moment. Any help would be greatly appreciated.

Edit: Some more information, the computer is still on (the LED light in the front are still on, music still plays if it was playing before. Just the monitor turns off.