View Full Version : [ubuntu] Low laptop LCD brightness on dual monitor setup

July 11th, 2011, 09:45 PM
Hi all,

I have installed Ubuntu 11.04 on my new Toshiba R630 laptop (laptop specification (http://uk.computers.toshiba-europe.com/innovation/jsp/SUPPORTSECTION/discontinuedProductPage.do?service=UK&toshibaShop=false&BV_UseBVCookie=yes&PRODUCT_ID=1089395)), everything is running great, I have installed webservers and all the staff I need for my daily work but I am having one problem.

I am using dual monitor setup but when I plug in my external monitor to the laptop, brightness on the laptop LCD is very low. When the external monitor is not plugged in, everything is working fine.

When I test the same in Windows 7, everything is working OK.

I really like Ubuntu and I would be very happy if I could use it all the day, but this is not possible without having this dual monitor setup working properly. If anyone can advice, it will be a big help for me.

Thank you


July 11th, 2011, 10:40 PM
Hi there,

I guess you are trying to set the brightness with the Fn keys. If so, try adding the brightness applet to one of the panels. It is a long shot, but there is still a chance it will work. http://ubuntuforums.org/images/icons/icon7.gif

July 14th, 2011, 01:30 PM
Hi sakishrist,

thank you very much for your reply. I have tried to use this applet, but it is not working for me (no effect when changing the brightness).

But what is even more strange is, that after restart of the laptop today the laptop LCD brightness is working fine even when using the external monitor. Maybe some of automated udpates helped, I really don't know, I haven't been changing anything in the config.

Even so, thank you very much for your care.


January 27th, 2012, 05:40 AM

I also installed Ubuntu 10.04 LTS in my Toshiba laptop(M60,very old,but I upgrade the memory),if I only use laptop's display,brightness is ok(not the best one),I can change the brightness from 1 to 7 by a tool called acpitool.
but when I connected a second monitor(SAMSUNG),external monitor is good,but laptop's display become very dark,still can see some pictures,but it is not good to work with it,and acpitool is not working now.

anybody has any updates?