-Use a different port of your graphics card (VGA, if available),
-While getting the black screen, disconnect and reconnect the video cable,
-Windows repair, using an Windows DVD,
-Testing a different graphics card,
-And the most funny: blindly updating the driver from device manager, using only the keyboard (Start, devmgmt.msc, Enter then Tab and arrows for automatically updating the driver). You'd need though an working system for following exactly the right steps. Otherwise the result might not be the expected one.