It depends on the ports on your video card and the ports on your monitor(s). There are too many possible combinations to list.
You could use a dual-link DVI cable which has 2 digital outputs, or an analog and digital out. You may need a DVI-->HDMI adapter for one of your monitors. You might need an active displayport adapter which allows a 'daisy-chain' of monitors if your video card supports it -- but that requires a displayport-out port on the monitor.
If one of the ports is d-sub, it would output to a single analog monitor.
If Windows does not recognize your configuration, you have to enter CCC, extend your Desktop to the display(s) and set your grouping. Be sure to save the profile.