Backlight switching off when logging into KDE Plasma Desktop
Happy New Year! I've got a problem with using KDE with Ubuntu 11.10 on an Acer 5336. There is a general problem with Acer laptops anyway when using Ubuntu in that, at boot, the backlight is switched off but there are solutions for that which means that I can get it switched on again and the login screen shows up fine.
If I log in to standard Ubuntu (Unity) there is no problem and the backlight stays on, but I wanted to try KDE, and when I try to login to the KDE Plasma Workspace, the backlight switches off again! It's a bit annoying, to be honest. To get the backlight working again requires running the command:
setpci -s 00:02.0 F4.b=00
I wrote a script for this and tried to get KDE Autostart to run it, but it won't because it needs to be run as root - result: my screen stays black!
Is there a way I can get KDE to run this script as root, or is there another way to run the command so that I can get my backlight on again? I can't see to input the command into a terminal, which would be the other way to do it, but it's a pain!
Any help would be appreciated.
Re: Backlight switching off when logging into KDE Plasma Desktop
For anyone else who is having this problem, here is an answer I found here:
Open a terminal and type in the terminal:
This will open rc.local file. Now at the bottom make sure it looks like below and save.
You should be fine, reboot and check it out.;)
sudo setpci -s 00:02.0 F4.B=00
My system's backlight comes back on fine during boot up with this modification. There's also a really helpful script for switching the backlight back on when you 'wake up' from suspend or hibernate