Originally Posted by
Novx
As long as they are both plugged in you should just be able to drag the windows over from your main to your secondary. The only thing that you need to keep in mind is that you must align the monitor in your display settings so that the system recognizes where it is.
For Nvidia:
Right Click on Desktop
Click Nvidia Control Panel
Go to 'Set up multiple displays'
Drag the monitor (should be labeled as '2') to the Left or Right of the Primary monitor (should be labeled as '1') depending on where you have it positioned on your desk.
For ATI: Sorry, no idea, but its probably something similar in the Catalyst Controller.