"extended desktop" mode). This mode allows you to use both screens independently and drag objects from one screen to the other, effectively doubling the amount of viewable work space.
1.Connect the external monitor, TV, or projector to the computer.
2.Under Pick a category, click Appearance and Themes.
3.Under Pick a task..., click the area you want to change, or under or pick a Control Panel icon, click Display.
4.In the Display Properties window, click the Settings tab.
NOTE: If you choose a resolution or color palette that is higher than the display supports, the settings adjust automatically to the closest supported values. For more information, see your operating system documentation.
5.Click the monitor 2 icon, click the Extend my Windows desktop... check box, and then click Apply.
6.Change Screen Area to the appropriate sizes for both displays and click Apply.
7.If prompted to restart the computer, click Apply the new color setting without restarting and click OK.
8.If prompted, click OK to resize your desktop.
9.If prompted, click Yes to keep the settings.
10.Click OK to close the Display Properties window.
To disable dual independent display mode:
1.Click the Settings tab in the Display Properties window.
2.Click the monitor 2 icon, uncheck the Extend my Windows desktop... option, and then click Apply.
If necessary, press <Fn><F8> to bring the screen image back to the computer display.
Swapping Primary and Secondary Displays
To swap your primary and secondary display designations (for example, to use your external monitor as your primary display after docking):
1.Click the Start button and click Control Panel.
2.Under Pick a category, click Appearance and Themes.
3.Under Pick a task..., click the area you want to change, or under or pick a Control Panel icon, click Display.
4.Click the Settings tab→ Advanced→ Displays tab.
See the documentation that came with your video card for additional information.