How do I change my screen resolution (screen size) on my Mac when connected to an active board or flat panel display?
The system often will not show the Display icon in the menubar even when you have an external display connected (a problem since Mac OS X 10.8). If you are having that problem, you can use the Display Menu application instead, which is located in the Applications folder on staff computers.
1. Navigate to your Applications folder in a finder window and double click on Display Menu.
2. The Display Menu icon will appear in the Finder menubar. Click and hold on the icon to reveal the drop down menu. Select Start on Login from the drop down menu. The Display Menu icon will then appear in the Finder menubar each time you log in to your computer.
The most stable resolution when connected to a projector is 1024 x 768 (60Hz). The most stable resolution when connected to a flat panel screen/display is 1280 x 720 (60Hz), with an aspect ratio of 16:9.
More details about resolution choices are available in KB article #239.