Assigning a Primary Dispaly

I have a MacBook Pro 13" running 10.6.4. I have a external Dell DVI flat panel connected to the Mac mini port on notebook. I purchased two Plugable USB 2.0 Graphics Adapter’s so I can run two other Dell DVI flat panels from the two remaining USB ports on the notebook. The problem is that I cannot figure out how to assign one of the monitors as the primary. How do I specifically assign one as the primary?

Hi David - Thanks for your question!

Yes, Apple hasn’t made this obvious. The trick is to open your Displays preference pane. Click on the Arrangement tab, and click & drag the menu bar from one display image to the other.

Here’s the icon for the Displays item in OS X’s System Preferences.

Click on the “Arrangement” will show something like this, with the white bar on top of the displays that’s currently set as primary.


If you click and drag that over to one of the other monitors, voila, OS X sets a new primary.


Note that I’ve seen scattered reports of difficulties when the OS X primary display is set to a display that comes and goes (and USB will do, when the devices comes and goes). I don’t know for certain if all those problems have been resolved.

Hope this helps. Please reply if there are any other follow-ups.

Thanks again for your purchase!