0

I used the acpi_osi= trick to make Xubuntu 14.04 work with my newly acquired CF-52 Mk 1 Toughbook. Among other things, this enabled it to control the LCD backlight brightness. This mostly works fine, but at 50%, the backlight brightness stops increasing.

These laptops are notorious for failing CCFL backlights. However, I am not experiencing flaring/flashing on startup, dimming over time, or inconsistent brightness. Is it possible that I have either limited the brightness to 50% somewhere without realizing it?

Thanks.

1 Answer 1

0

Download xblacklight from Ubuntu software store.

Xbacklight is used to adjust the backlight brightness where supported. It finds all outputs on the X server supporting backlight brightness control and changes them all in the same way.

   -get   Print out the current backlight brightness of each  output  with
          such a control. The brightness is represented as a percentage of
          the maximum brightness supported.

   -set percent
          Sets each backlight brightness to the specified level.

   -inc percent
          Increases brightness by the specified amount.

   -dec percent
          Decreases brightness by the specified amount.

   -help  Print out a summary of the usage and exit.

   -time milliseconds
          Length of time to spend fading the backlight between old and new
          value.  Default is 200.

   -steps number
          Number of steps to take while fading. Default is 20.
9
  • XBackLight produces no change between 50.0% and 75.0% or 100.0%, just like the Fn-key or GUI controls. Mar 4, 2016 at 3:52
  • Are you on Ubuntu or Xubuntu? Mar 4, 2016 at 4:55
  • Xubuntu, as stated in my question. Mar 4, 2016 at 15:37
  • Are you on the latest version? I opened up my terminal and used commands with xbacklight and it worked for me. Did you install xbacklight from terminal or the USC? Mar 4, 2016 at 18:47
  • Have you tried this: 1. sudo nano /etc/rc.local 2. add this line to the file (substitute X with the desired level of brightness): echo X > /sys/class/backlight/intel_backlight/brightness Mar 4, 2016 at 18:49

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.