I have 3 dg45fc boards and 3 external monitors. The monitors provide DVI connections. We are using the hdmi output port on the dg45fc board and a hdmi to DVI cable.
When I boot the machines (win XP), I see the intel splash screen and the windows logo. If I press F8 annd select Safe Mode, I get a picture. If I dont press F8, the monitor goes dark (no picture).
To complicate matters, one of the machines (an older one), has a driver which is older than the 2 other machines, which have recently been updated to the latest drivers. I am reluctant to update the single machine for fear of losing picture on that one as well.
Have you tried using "VGA Mode", also in the F8 menu? From there you should be able to reset your video settings and get your image back, at which point you can reboot normally and set your desired resolution. If this doesn't work, try rebooting in safe mode, uninstalling your video drivers completely, and rebooting with the default Windows drivers. If that works, you can try reinstalling the latest drivers. If nothing else works, try a Linux boot CD (live mode, no install required) and see if your video is correct there.