How to switch off a screen laptop under Linux

This post describes how to save power on a laptop running Linux by switching off the screen backlight. The instructions are tested on a Dell Latitude C810 running Ubuntu Linux 5.10. The first part is straightforward: set the correct governor for the CPU frequency with the following command. echo powersave > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor This is executed …