Connecting weird displays used to be an ordeal. But, if you’re using a Raspberry Pi 4 or 400, paired with the “desktop” Raspberry Pi OS (not the “Lite” variant)…and with a little bit of luck…everything is much simpler now. Quite a few of these displays are now plug-and-play! A stable and usable resolution is often negotiated, and only minor adjustments may be needed.
This isn’t always the case though. If you find a display that won’t work automatically, the following explains how to work things out manually.
The Raspberry Pi 4 and 400 have two HDMI outputs. If two displays are connected, and if either one fails to sync, often that will spoil the party for both…you’ll get no video to either screen. When trying out new displays, connect just one at a time and reboot. For any that won’t sync, follow the steps on the next page. Once resolved, you can configure distinct settings for each HDMI port (also explained there).
With a display working for the first time, you might need to adjust some stuff like rotation or turning off the black border. Settings for these can be found under the Pi (system) menu…
Pi→Preferences→Raspberry Pi Configuration and (on Pi 4 or 400) Screen Configuration
The Pi menu can’t be seen on round displays because it’s clipped off the edge, but can still be accessed by moving the mouse all the way up and left and clicking. The pixels are there, you just can’t see them.
In the Raspberry Pi Configuration tool, click the Display tab to access overscan (border) settings, and — if the screen supports different modes — configure the display resolution.
The Screen Configuration tool lets you change which way is “up.” This is handy if you want to use an old monitor in a vertical “portrait” orientation — playing Dig Dug, for example. If you have multiple displays connected, you can also inform the system of their physical arrangement here, so the mouse and windows move between them more naturally.
As mentioned above, a handful of displays still won’t play nice. Or you might have a need for the “Lite” Raspberry Pi OS, or a third-party operating system. In these situations you can still get in there and do it The Old-Fashioned Way.