Is it possible to run a dual-monitor setup with my integrated Nvidia 6100 if I install a discrete card that has a single VGA output? Or would that require a discrete card with 2 outputs and disable the integrated?
I Think you can. Windows has no problem with different video adapters; be it integrated or discrete. Of course the integrated adapter will usually not be as strong as the discrete. For sandy bridge, I am planning on using a discrete card for my gaming monitor, and the integrated adapter for my secondary monitor.