Luke Ryan Jernejcic

Change The Primary Monitor In A Dual-Monitor OS-X Setup

May 28, 2012

Do to some unexpected circumstance I ended up loosing my 2008 24″ iMac this week (my work machine), leaving me with my old 2006 MacBook Pro (my personal machine, the first of the Intel models). I have been intending to upgrade my personal equipment, but have been waiting for Apple to release the new models (been waiting since October). Well now I am more motivated to get the process started.

Dell U2412M LED Monitor

First thing, this week I got a new monitor, the Dell UltraSharp U2412M 24″ LED LCD Monitor off Amazon. I am still working out my opinion of the monitor and may write up a review of it at a later time.

First issue I come up with is that the external monitor is always secondary to the MBP display. Obviously with a 15″ MBP and a 24″ monitor, I’m going to be using the 24″ monitor primarily. I want the menu bar on the external monitor. I want everything to default to the nice, big monitor! At first I wrote it off; I didn’t see any method to get it done and did not have time to research it.

Today I had some time and googled it, figuring there had to be a way even if through 3rd party software. Turns out it’s pretty darn easy and it is indeed built right into OS X. Here we go:

Step 1: Open up the Displays page in the Settings app.

The System Preferences app

Step 2: See that little white bar on the tiny monitor below. It symbolizes the primary screen and as it turns out that you can drag it between monitors. Do so and you will see the primary monitor change.

The Display Window in the System Preferences.

Step 3: Never mind, you’re done!

Like many things in computers, once you know what do you it is surprisingly easy. I am glad this worked as Photoshop wasn’t letting me drag some things between the monitor and it would have been exceptionally annoying.


Written by Luke Ryan Jernejcic who lives and works in Austin Texas building useful things. Follow him on Twitter