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I've installed Ubuntu 12.04 on a Lenovo G500s Laptop. The screen is scrambled/shows weird artefacts during boot but that doesn't really bother me. What does is this:

The screen's brightness is always 0% on boot, which means that it is pitch black.

I've already searched this site and found two suggestions:

  • echo 50 > /sys/class/backlight/acpi_video0/brightness in /etc/rc.local
  • /usr/bin/xbacklight -set 50 in /etc/rc.local

Both work fine (affect the screen's brightness) when I execute them from the Terminal, but when I put either of them in /etc/rc.local the display will still be pitch black on the login screen after a reboot.

Any suggestions?

share|improve this question
G500s user! An ad hoc fix is to add sleep 2 before echo ... in /etc/rc.local. This should work for you. A more consistent solution is (should be) this one of mine: – S Prasanth Nov 12 '13 at 6:03
Thanks a lot - I just tried that and it worked. :) – domsson Nov 15 '13 at 15:04

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