16.04 ; power off discrete graphics (ATI/AMD)

Question

On 12.04 I used to utilize this procedure, to power off my ATI graphics and prevent my system from overheating, it worked fine. After installing 16.04, I've been trying everything I could find on the net, but no solution. My system runs extremely hot, causing the fans to run at max almost all the time. Can anybody come up with a little hack to shutdown that discrete ATI Radeon card?

thanks. M.Schoofs

System: HP Pavilion dv7-6190ed (FW F.18) [AMD/ATI] Whistler [Radeon HD 6730M/6770M/7690M XT]

Solution 1

Following Neni's answer, I had kernel panic after sleep. I solved my problem by adding radeon.modeset=0 amdgpu.runpm=0 acpi_backlight=intel_backlight to GRUB_CMDLINE_LINUX_DEFAULT

To edit file :

sudo nano /etc/default/grub

Find line :

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

And replace with :

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash radeon.modeset=0 amdgpu.runpm=0 acpi_backlight=intel_backlight"

To regenerate config :

sudo update-grub

Reboot :

sudo reboot

What those options do :

• radeon.modeset=0 disables radeon driver
• amdgpu.runpm=0 disables the power management from amdgpu driver
• acpi_backlight=intel_backlight uses intel driver to control laptop screen backlight

---

Official bug report suggests as a workaround either manually install newer kernel (which you would have to manually update) or run those steps :

1. /etc/default/grub: Add amdgpu.runpm=0 to GRUB_CMDLINE_LINUX_DEFAULT
   Included above.

2. /etc/rc.local: Add the following command:

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

   This step caused my system to freeze on shutdown so I just skipped it.

3. /etc/X11/xorg.conf: Create the file if it doesn't exist, and add the following in order to get the backlight controls working (otherwise it would be misdetected):

   Section "Device"
       Identifier "Card0"
       Driver "intel"
       Option "Backlight" "intel_backlight"
   EndSection
   

   This step is replaced replaced above by acpi_backlight=intel_backlight

Solution 2

Check graphic drivers which are in use (radeon/amdgpu should be listed):

lspci -nnk | grep -i vga -A3 | grep 'in use'

Note: If amdgpu is listed, replace radeon with amdgpu in the instructions below!

---

Open the following file:

gksudo gedit /etc/default/grub

Modify the following line by adding radeon.modeset=0:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash radeon.modeset=0"

Save and Exit

---

Back to Terminal:

sudo update-grub
sudo reboot

---

Check again which graphic drivers are in use (radeon/amdgpu should not be listed anymore):

lspci -nnk | grep -i vga -A3 | grep 'in use'

Now, your ATI/AMD graphic card is disabled and your computer works only with the Intel graphics. The fan speed should significantly decrease.

Comments

[Mookey]

What if the driver in use is Intel onboard (i915) instead of ATI's discreet, but the fan still runs and heats up. Could I still apply the same change to grub? Would it work? It started happening when I upgraded kernel build to 4.4.0.22 from 4.4.0.21 (battery life reduced).

[Neni]

check if your discrete card is powered: sudo cat /sys/kernel/debug/vgaswitcheroo/switch... since the kernel update it is powered without beeing in use... if so, then do the above instructions, so far the only thing that works for me...

[Mookey]

4.4.0.21: 0:IGD:+:Pwr:0000:00:02.0 1:DIS: :DynOff:0000:04:00.0; 4.4.0.22: 0:IGD:+:Pwr:0000:00:02.0 1:DIS: :Pwr:0000:04:00.0

[Mookey]

So both kernels are the same, yet there's a considerable difference.

[Dmitry Koroliov]

It seems, that the GPU remains powered after these procedures. I followed the answer and at first, during the first 5 min of the laptop's work, it looked like the fan's speed dropped significantly. But then it turned out to be not. I think, that the problem is still with the GPU because the system monitor shows the CPU loaded to 1-2%.

[Dmitry Koroliov]

for some reason passing radeon.runpm=0 has helped though the card remains in the list output by the lspci -nnk | grep -i vga -A3 | grep 'in use'. But the laptop does not overheat any more

[Neni]

The fan problem only appeared with kernel version 4.4.0-22!

[sherrellbc]

@Neni, I seem to have the opposite problem. My system is using the integrated graphics by default, despite enumerating the discrete PCI GPU. The output of the above sys debug node indicates that the card is powered off. Do you know a method for enabling the card?

[ecth]

What AMD chips do you have? My iGPU is in a Richland APU, the dGPU is 7970m (GCN1.0), so I can't use the new AMD drivers. But I'll give it a shot.

[Sour LeangChhean]

Greate answer.!!!

[Dave]

This worked.. Thanks!

[Himanshujaggi]

Thanks. It worked for me.