This tutorial only applies to PC (x86_64) installs. On Raspberry Pi, the video output is picked automatically.
On a PC — a laptop in particular — Recalbox can send its picture to an external screen rather than to the main detected display. This is useful when the internal screen is broken, or when you want to force a specific output and its resolution.
Connect to your Recalbox over SSH and run:
xrandr
The command lists every video output, its state and the resolutions it accepts:
Screen 0: minimum 8 x 8, current 1920 x 1080, maximum 32767 x 32767
DVI-D-0 disconnected primary
HDMI-0 connected 1920x1080+0+0 598mm x 336mm
2560x1440 59.95 + 69.93
1920x1080 60.00* 59.94 50.00
1280x720 60.00 59.94 50.00
DP-5 connected
2560x1440 59.95 +
1920x1080 59.94 50.00
1280x720 59.94 50.00
Note the exact name of the output to use (HDMI-0, DP-5, eDP-1…) along with the resolution and refresh rate you want.
recalbox.confOpen the recalbox.conf file and fill in the following block:
## Preferred external screen, retrieved over ssh with: xrandr
system.externalscreen.prefered=DP-5
## Force the resolution of that screen, e.g. 1920x1080
system.externalscreen.forceresolution=1920x1080
## Force the frequency of that screen, e.g. 60.00
system.externalscreen.forcefrequency=59.94
Those three lines are commented out by default with a leading
;: remove that character on each of the lines you fill in.
The three settings are independent: you may set system.externalscreen.prefered only and let Recalbox choose the resolution.
Reboot to apply the configuration.
If you end up with no picture, edit recalbox.conf from another device (web manager, SSH, or by mounting the disk on a computer) and comment the lines back out.
Need help? Join the Recalbox Discord, with the output of the
xrandrcommand.