Live in i3, live in the terminal. No GUI for changing display properties. So, here's a CLI command to set a new screen resolution.
xrandr lingo, a "mode" is approximately a "resolution" and an "output" is a "monitor".
xrandr # list available outputs and modes cvt 3840 2160 60 # calculate mode line (for 3840x2160) xrandr --newmode
# create new mode xrandr --addmode
man pages for extra help.
Discover screen capability
First, discover what displays and resolutions are available to you. Do that with:
You'll get an output something like:
eDP-1 connected primary 2560x1440+0+0 (normal left inverted right x axis y axis) 344mm x 194mm 2560x1440 165.00*+ 40.00 + 1920x1440 85.00 75.00 60.00 ...
Look for preconnected displays that are already ready to display things. Connecting displays can be a chore in itself, depending on circumstances. We won't cover that here.
Note the output name -- in this case
You may not have the desired mode listed for the output. But the output may support another mode.
xrandr may tell you about the min or max resolutions.
Once you know your resolution, xorg wants you to specify it as a new mode. To get to that step, you need a modeline to feed to it. To get the modeline, use the
cvt command. Feed it
cvt 3840 2160 60 on this monitor, I get:
# 3840x2160 59.98 Hz (CVT 8.29M9) hsync: 134.18 kHz; pclk: 712.75 MHz Modeline "3840x2160_60.00" 712.75 3840 4160 4576 5312 2160 2163 2168 2237 -hsync +vsync
The text after "Modeline" is what you need for the next step.
To get that mode added to the output, it requires a two-stepper:
xrandr --newmode "3840x2160_60.00" 712.75 3840 4160 4576 5312 2160 2163 2168 2237 -hsync +vsync xrandr --addmode eDP-1 3840x2160_60.00
This creates a new mode called "3840x2160_60.00" and associates it with
Set the resolution
Now that you have the mode set up and associated with the output, use
xrandr to set the output to use that mode.
xrandr --output eDP-1 --mode 3840x2160_60.00
If it works, your monitor will immediately switch into the requested resolution. Say hello to tiny 4k terminal text.
Persist resolution choice
Now if you want to persist this change so you don't have to type the
xrandr commands in the next time you reboot, then add the
--output commands to