This has been an unsolved issue for me since I installed Windows 7 last year. I've read numerous articles, none of which have solved the problem.
I have Windows 7 64-bit installed on a Core 2 Duo 2.2 GHz, 2GB RAM, and using a GeForce 9800GT video card.
PROBLEM: As soon as I connect a second monitor (DVI to HDMI or DVI to VGA) the original monitor goes black and there is no display on the 2nd, newly connected, display. If I disconnect the second display, the 1st monitor remains black until restart. Note: I had both connected during the original install and the install could not finish as the monitors went blank, so I had to reinstall with only 1 monitor connected.
I have the latest Nvidia drivers installed and all critial updates installed. How can this be solved? Thanks.