- 1). Identify the connector on your external display. The MacBook uses the Mini DVI port to connect to external and additional displays, so you need to use an adapter that connects from the Mini DVI port to your new display. If your display uses a 15-pin VGA plug, you will need a Mini DVI-to-VGA adapter. If your display uses a 24-pin DVI plug, you will need a Mini DVI-to-DVI adapter. Both adapters are easily found at most computer supply stores.
- 2). Connect your new display. Connect the plug from your external display to the matching end of the Mini DVI adapter. Then plug the Mini-DVI end into the correct port on your MacBook.
- 3). Detect the new display. Go into your system preferences under the apple menu on your desktop. Select "Displays." In the window that appears, click on "detect displays" and your MacBook should recognize the new display connected to your laptop. Once detected, you should be able to drag elements across both screens as if it were one larger screen.
- 4). Arrange your monitors. In the same system preferences window, click "arrangement." A diagram of your two displays will appear. Drag the two display representations into the same arrangement you plan to use. For instance, if your MacBook is on the left and the external display is on the right, make the diagram represent that so your MacBook knows your physical setup and can reflect your movements properly.
- 5). Mirror displays. In the same system preferences window, you can select a check box for "mirror displays." When this option is checked, both displays reflect as copies of a single desktop. This may be useful for running demonstrations where you need a larger display.
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