Does it happen on screen saver?
does it go on standby after like an hour or 15 mins?
does windows shut off the video card to save power?
Check those really quick, what I do is just have windows shut down monitors I change the preformance to full power and change it so it doesnt turn off the video card at all to save power. Let me know if it helps
Screen saver is disabled
The screen will never go black
This hasn't happened since I stopped leaving windows media player open.