I have a Asus Rog GL702VS-RS71 and I am having trouble with adjusting the brightness I have tried everything online that I could find but to no result.

Have tried the following... Installing xbacklight and adjusting the settings on terminal(nothing happens)

gone into sudo nano /etc/default/grub and done the following below each with no result.. And yes I have sudo update-grub


GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi="

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_video0="

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=acpi_osi"

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=acpi_backlight=native"


GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux acpi_backlight=vendor"


GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=acpi_backlight=native intel_idle.max_cstate=1"

The splash screen shows with the brightness indicator going up and down but no solutions I've tried have worked yet. the battery applet in the bottom right corner doesn't do anything either if I move the slider up or down for the brightness

the only brightness that works when using the brightness keys is my keyboard brightness but theres already seperate keys for that and they work fine.. :/

PLEASE if you know the answer to this would appreciate the help so much!! As this is burning my eyes at max brightness..

  • Related questions: askubuntu.com/q/1045624/307523 and askubuntu.com/a/715310/307523 Jun 14, 2018 at 23:30
  • Still having an issue.... Anyone??
    – RUSTY
    Jun 27, 2018 at 3:44
  • Can you update your question with the output from ll /sys/class/backlight? Jun 27, 2018 at 10:03
  • ll /sys/class/backlight total 0 drwxr-xr-x 2 root root 0 Jun 29 19:23 ./ drwxr-xr-x 68 root root 0 Jun 29 19:22 ../ lrwxrwxrwx 1 root root 0 Jun 29 19:22 acpi_video0 -> ../../devices/pci0000:00/0000:00:01.0/0000:01:00.0/backlight/acpi_video0/
    – RUSTY
    Jun 29, 2018 at 7:24
  • What kind(s) of graphic card(s) does your laptop have? Jun 29, 2018 at 10:25

1 Answer 1


Software solution

In the question and in comments OP has tried many different hardware solutions to no avail. This leaves software solutions which aren't as effective but better than nothing. This script can be adapted for all monitors:


# NAME: alien
# PATH: /mnt/e/bin
# DESC: Set brightness of Alien Laptop
# DATE: Dec 9, 2017. Modified July 21, 2018.

# NOTE: Monitor name changes with driver used: nVidia = "eDP-1-1"
#                                             Nouveau = "eDP-1"
#                                               Intel = "eDP1"

AllMonitors=`xrandr -q | grep -v disconnected | grep connected | awk '{print $1}'`
echo All Monitors: $AllMonitors
for s in $AllMonitors; do
    if case ${s} in *"${MonitorName}"*) true;; *) false;; esac; then
        printf %s\\n "'${s}' contains '${MonitorName}'"
        printf %s\\n "'${s}' does not contain '${MonitorName}'"
echo Full Monitor: $FullMonitor

if [[ $# -ne 1 ]]; then
    xrandr --verbose | grep -A5 "^$FullMonitor" > /tmp/alien
    head -n1 /tmp/alien
    echo "$(tput setaf 6)" ; tail -n1 /tmp/alien ; echo "$(tput sgr0)"
    rm /tmp/alien
    echo 'One argument required for brightness level, e.g. "alien .63"'
    echo 'will set brightness level of Alien display to level .63 using xrandr'
    exit 1

xrandr --output "$FullMonitor" --brightness "$1"

The script above was written for a three monitor system and addresses the laptop screen. Two other scripts (not listed here) are called "Sony" and "Toshiba" for two external HDMI monitors. The laptop can have Intel driver for i7-6700 HQ HD 530 graphics iGPU, nVidia GTX 970M GPU with different xrandr screen names depending on nVidia Proprietary Graphics driver or Nouveau Open Source driver.

Because the system has a total of 9 different xrandr screen names, three names for each screen, the script is flexible depending on how the machine has been booted.

To adapt this script to your needs:

  • Rename script, eg change alien to msi
  • Rename eDP, use xrandr to get list of all monitor names and select appropriate prefix. Enter prefix only into the script. It will find the -1 suffix automatically.
  • When calling pass parameter one for brightness level; .75 = 75%, .3 = 30%, etc.

Keep checking new kernels for hardware support

Use these commands to check if hardware is supported after a kernel update:

$ ls /sys/class/backlight
$ cat /sys/class/backlight/intel_backlight/*brightness*
  • The first 3000 is the actual brightness
  • The second 3000 is the last attempt brightness change
  • 7500 is the maximum brightness level for your hardware

To attempt to change hardware brightness level use:

$ echo 2500 | sudo tee /sys/class/backlight/intel_backlight/brightness

If hardware is supported you will see a change:

$ cat /sys/class/backlight/intel_backlight/*brightness*
  • Thank you very much for your time WinEunuuchs2Unix very much appreciate your help
    – RUSTY
    Jul 23, 2018 at 6:18

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