This problem occured when my 4-yr old Lattitude D810 was working normally after not being used for 5 weeks.  When coming out of sleep mode, the computer screen went black (truly black, does not appear to be a backlight issue).  The screen will turn black on any setting higher than 640x480, 8-bit colors. 

Things that have been tried:

1) Changing resolution to a variety of settings (800x600, 1024x768, and higher)

2) Deleting drivers for the monitor and video card and letting windows reinstall them (also updating video drivers)

3) Turning off hardware video acceleration

4) BIOS is up to date

5) Installing windows updates and dell driver updates

Essentially when any video change is made, no matter how minor, the screen will turn black and have to be restarted, but the laptop appears to be functioning normally otherwise.  Doing a hard drive wipe and reinstall are out of the question for the time being, and I'm wondering if anyone has a suggestion other than this.  Thanks