Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have an HDTV that I'm hooking up via DVI to HDMI from my Mac mini. In my struggle to eliminate overscan I managed to set the screen resolution to something not supported by the tv. How do I change the resolution without that screen attached?

Specifically my tv says it's "720p and 1366 x 768 Resolution". The 720p resolution option in OS X made for a ton of overscan (couldn't see menubar or dock at all). So I tried something x 768 and managed to shoot myself in the foot with an unsupported resolution. I thought it was okay to experiment since a resolution change times out if you don't accept it. Apparently that didn't happen for some reason. I've already deleted the in /Library/Preferences as I saw suggested in other places, with no effect.

share|improve this question
I should add that if I boot with the TV attached I get a signal, but once I log in again it switches to the unsupported resolution. – Brad Oct 15 '10 at 13:37
When you write "deleted the in /Library/Preferences", do you mean what I suggested? Filename and path are different, therefore I have to ask; since you didn't follow up on my answer. – Daniel Beck Oct 22 '10 at 20:49

You can "gather windows" in the Displays preference pane when the non-functioning display is attached, so you can set its properties from the display that works.

If the attached display is your only one and you have access to your user's files (e.g. second display that works), the preferences are stored in


where [UUID] is, well, a UUID and looks somewhat like 598781DD-929A-5CA7-FFED-EF19A1B625F8.

You can try editing this file using Property List Editor (part of the Apple Developer Tools) (I think the relevant entries are Unmirrored Height and Unmirrored Width, it might be difficult to find the correct list entry from VendorID etc. alone however).

You can also trash or rename it, resetting all screen configuration you may have had.

share|improve this answer
The mini only has one video output, hence the issue. – Brad Oct 16 '10 at 5:42
@Brad sorry about that. added info where OS X seems to store the display preferences. – Daniel Beck Oct 16 '10 at 10:19

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.