If you let it load, does it play the Windows startup sound? If it does (assuming you haven't disabled it), it would mean that Windows is loading and getting to the login screen.
Am I right in say that that card has 2 DVI connectors and a mini HDMI?
If so, try connecting the other DVI to the monitor. If that doesn't work, try the mini-HDMI.
It sounds like everything is working till Windows loads the display driver, then when the display driver loads, it sends the video signal to a different port.