7

I could disable ATI discrete graphics in Ubuntu 13.10 with this command:

echo OFF > /sys/kernel/debug/vgaswitcheroo/switch

But in Ubuntu 14.04 it does not work. cat /sys/kernel/debug/vgaswitcheroo/switch shows the same:

0:IGD:+:DynPwr:0000:01:05.0 
1:DIS-Audio: :Pwr:0000:02:00.1 
2:DIS: :DynPwr:0000:02:00.0

What should I do in Ubuntu 14.04?

bain
  • 12,200
user270817
  • 71

3 Answers3

6

In this version of Ubuntu, Dynamic Radeon Drivers are included and activated so that the old solution that you mention does not work.

To operate the old solution you can edit the file /etc/default/grub.

In this file you can add the option radeon.runpm=0 in the call to the current kernel (usually after ro quiet splash).

Alternatively, you can also add radeon.runpm=0 to the value of the variable GRUB_CMDLINE_LINUX_DEFAULT, then save and run sudo update-grub.

user3267589
  • 81
  • 2
0

This worked for me....

Enter this 

"echo OFF > /sys/kernel/debug/vgaswitcheroo/switch"

twice after

"echo DIS > /sys/kernel/debug/vgaswitcheroo/switch"

It then shows the discrete graphics card as off instead of dynoff. And works exactly like it used to in previous versions.

guntbert
  • 13,475
Navarurh
  • 1
0

I have the same issue and the command bellow seems to be working

sudo aticonfig --initial --px-igpu --effective=startup

then restart. (I'm using the fglrx driver)

Foad
  • 101