The following Apple portables support the use of an external display or projector while the internal display is closed. MacBook Pro MacBook PowerBook G4 MacBook Air This is known as “closed clamshell” or “closed display” mode. To enable closed clamshell (display closed) mode, please use the steps below: Note: iBooks do not support closed clamshell mode. You should not close the display lid of an iBook computer while using an external keyboard, mouse, and monitor.

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Apple Portables: How to use your computer in closed clamshell (display closed) mode with an external display

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