As I do this, the MacBook's own screen remains free for me to use any way I see fit. If I choose to extend my desktop rather than mirror it, then I can use the Vizio television to display anything I want (PowerPoint, Keynote, Hulu over Safari, etc). Using the MacBook's video output port brings up additional options in the Display settings in System Preferences. This behavior should be similar in Windows as well.įor example: Whenever I attach my MacBook to an external video source, say a Vizio television, I typically end up using Apple's mini-DVI to VGA adapter. In other words, I do not think that what you are looking for is a PowerPoint feature per se. This is the same behavior you see on a MacBook when you extend your desktop via an external monitor. Per suggestion: The way I have seen a presenter switch to an application away from PowerPoint without being displayed on the presentation video output is to do it on a separate screen when you extend your desktop via a projector.