Ubuntu – How to get the ASUS laptop to start at the right brightness level


I want to make it so my laptop starts at a low brightness level, which is comfortable for my eyes and easy on the laptop's battery. I found some instructions here on AskUbuntu, and so by using this command:

cat /sys/class/backlight/intel_backlight/brightness

… I discovered that the maximum brightness is 4080 and the ideal brightness that I want to have my laptop default to is 700. So, I edited my /etc/rc.local file to have the following line in it:

echo 700 > /sys/class/backlight/acpi_video0/brightness

However, that didn't work. So, after a little more research, I tried this line:

echo 700 > /sys/class/backlight/intel_backlight/brightness

But that also changed nothing.

Now I'm a bit stuck. How do I get my brightness to start at the right level when I log in on my laptop?

Note: It seems that this problem may be made worse by another more general issue of commands not running at startup, which I've asked about in a separate question. I think some of the answers suggested so far may actually work in principle, but I can't verify any of them unless I'm sure my startup programs are executing at all.

Best Answer

  • I had the same issue.

    Solution = xbacklight:

    Install xbacklight:

    sudo apt-get install xbacklight

    Then add "xbacklight -set x" (where 'x' = 0 to 100 desired brightness) to the startup applications via dashboard. For example, xbacklight -set 50.

    This works with UX32VD and UX31A Asus Ultrabooks.