I've just bought a new 750 Ti, and unlike my old 5750 which had 2x DVI-I ports, this has 1x DVI-I and 1x DVI-D, but I'm not sure if that's causing the problem here:
I've also noticed that my two DVI cables are different... one converts to VGA which works fine, and the other is a regular DVI lead which doesn't:
Does anyone please know what could be causing this problem? I've tried switching around the cables into both ports, and either way the monitor with the DVI lead doesn't work - but the DVI to VGA monitor works regardless of which of the ports it's connected to.
Similarly when I plug the DVI to VGA cable into the other monitor, it works fine, so I'm thinking the problem isn't with the monitor either.
Update: oddly, the two monitors are now working just fine, however, the one still doesn't work in the BIOS/during boot (not ideal since it's the main monitor, the other is very much secondary) and also right before loading into Windows, both monitors turn off for around 10 seconds... not quite sure if there's any way to fix it though.