|Since it's doing it also during bios setup it's not a windows video setting problem.|
Since you can go ahead and enter the password even thouigh the screen is blank and then hear the windows sounds I would guess the problem is the monitor and not the video card since a flakey card might cause an error message that prevents windows from loading.
But don't spend money on a new monitor based on my guess. First try another monitor and see if the problem goes away.
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