Laptop backlight stays at 100%

[monte]

Hi, I have searched extensively on this issue and have been unable to found a problem/solution similiar to mine. I have a Gateway NV78 laptop equipped with a Core 2 Duo and Intel Integrated Graphics Mobile 4. lspci stats i915 kernel driver is in use. My FN + Keys will not adjust the backlight. Running off the battery does not dim the backlight either. Obivously this reduce battery life quite a bit and I would really like to keep Kubuntu as m y primary and only os on my laptop. In advance, I appreciate any help.

[Snowhog]

Re: Laptop backlight stays at 100%

It should be, but check to see if the package acpi-support is installed.

[monte]

Re: Laptop backlight stays at 100%

Yes acpi-support is installed.

[Snowhog]

Re: Laptop backlight stays at 100%

Do you know how to edit 'on the fly' the kernel boot line when you are presented with the Grub menu? Are you presented with the Grub menu?

[monte]

Re: Laptop backlight stays at 100%

By on the fly do you mean when at the menu (was it e or c) to edit grub? If so vaguely, mostly messed with grub-legacy. Havent used linux in awhile, so im in refresh mode right now. shoot your idea anyhow, nothing a quick google search cant solve. Much appreciated.

[Snowhog]

Re: Laptop backlight stays at 100%

From the Grub menu, highlight the kernel entry you want to boot from if you have more than one and press 'e' to edit. Edit the kernel line and add acpi=off

Read the instructions on the screen (bottom) to continue to boot. This will use the acpi=off kernel boot option 'for that session only' - no permanent change made.

After you log in to your dekstop, see if the brightness keys work. If they do, then make sure everything else still does as well. You can then modify the /etc/default/grub file (as Root) and add this option to the line:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" so it reads GRUB_CMDLINE_LINUX_DEFAULT="quiet splash apci=off"

After the change to this file, in a console run:

sudo update-grub

[monte]

Re: Laptop backlight stays at 100%

N0 the problem still exists. has to be somthing going on here.
*update*Correction, i was able to adjust the brightness, however i lose functionality of wireless device and im sure other features. with acpi=off needed to do update-grub. it seems to have retained my brightness level from when i adjusted it with acpi off.