Thursday, March 26, 2020

Overscan monitor issues on HP 2509m

If you're noticing that you can't see the title bar and the bottom status bar, it's because the overscan settings need to be changed.

The instructions at the bottom of this blog post (https://ishan.co/external-monitor-underscan) worked for me:

 1. Make a backup of the current file:
 2. cp /var/db/.com.apple.iokit.graphics /tmp/.com.apple.iokit.graphics.backup
 3. With the “troubled” monitor connected, open Display Preferences, and change its settings. For example, I changed the rotation.
 4. Run the “diff” command to see what had changed in that file after you made the changes:

56a57,58
>   framebuffer-rotation
>   0
58c60
<   10000
---
>   9000

5. I derived 9000 from -10% less overscan, which works great!

The process is automated in this Bashmatic script! (https://github.com/pioneerworks/lib-bash/blob/master/lib/osx.sh#L41-L53)