How do I detect displays in OS X Mavericks? The Systems Preferences option to detect displays seems to be missing.
While in the "Displays" Systems Preferences panel, press the "option" key and the "Detect Displays" button will appear when using OS X Mavericks.
This was tested to work in OS X 10.9 and 10.9.1. Your mileage may vary in other versions.
- http://reviews.cnet.com/8301-13727_7-57601545-263/how-to-detect-displays-in-os-x-10.8/ (original source, but a bit more verbose)