RyanR
Posts: 5
Joined: Thu Oct 17, 2019 10:47 am

Pi 4 Overscan for Second Monitor Only

Fri Feb 14, 2020 9:23 am

Hey guys,

I have recently configured a dual-display setup for use in a project using a Raspberry Pi 4, on the latest version of Raspbian. I am currently using two 24" HDMI monitors, but will be moving to small panels for when we deploy the project. My issue is that the second monitor has a black border, due to the overscan settings, but the primary monitor is perfect.

I can adjust these settings in /boot/config.txt. However, the changes apply to both monitors, not just one; so if I try to overscan the black borders away from the second monitor, it just creates new borders on the monitor that was perfect. These settings seem to be global for all monitors, and not monitor specific.

Is there anything I can do in the configuration file that lets me activate an overscan for just the second monitor, or are there any Pi hacks that I could use to "bodge" it?

Any help would be appreciated!

Thanks,
Ryan

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 24926
Joined: Sat Jul 30, 2011 7:41 pm

Re: Pi 4 Overscan for Second Monitor Only

Fri Feb 14, 2020 10:12 am

Taken a quick look at the firmware code and it appear that overscan cannot be set for individual displays. It's either on or off globally.
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RyanR
Posts: 5
Joined: Thu Oct 17, 2019 10:47 am

Re: Pi 4 Overscan for Second Monitor Only

Fri Feb 14, 2020 10:13 am

Thanks for the reply, I did a bit more digging and it turns out it was an easy fix!

For anyone else wondering, just enable 'disable_overscan' in the boot config:

'sudo vi /boot/config.txt'
Change '#disable_overscan=1'
To 'disable_overscan=1'.

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