Backlight/Brightness always at 100% NVIDIA RTX 2080 Mobile 535.154.05, Linux Mint 21.3 (Ubuntu 22.04)

You need to load the module
sudo modprobe acpi_call

Thanks again for your help and patience.

I can only run these commands when I’m su because I get a “No authorization” message.

sudo su
sudo modprobe acpi_call echo '\_SB.PCI0.PEG0.PEGP.LCD0._BCM 0x1e' > /proc/acpi/call
sudo modprobe acpi_call echo '\_SB.PCI0.GFX0.LCD0._BCM 0x1e' > /proc/acpi/call


sudo modprobe acpi_call
sudo su
echo '\_SB.PCI0.PEG0.PEGP.LCD0._BCM 0x1e' > /proc/acpi/call
echo '\_SB.PCI0.GFX0.LCD0._BCM 0x1e' > /proc/acpi/call

makes no difference.

It seems that the brightness control of Clevo is a tough nut to crack.
I have a similar problem. here
@generix hey bro, can you tell me can you tell me what these command " echo '\_SB.PCI0.GFX0.LCD0._BCM 0x1e' > /proc/acpi/call" " echo '\_SB.PCI0.PEG0.PEGP.LCD0._BCM 0x1e' > /proc/acpi/call" did?
I will try it in my laptop, maybe it has different effects in pascal card.

Those are direct acpi method calls, _BCM is the Backlight Control Method, 0x1e=30 decimal, setting to 30% brightness. those are specific to the acpi bios of a machine, so likely don’t exist on your machine, having a different path. In general, those should do the same as setting “acpi_backlight=video” and then using the backlight handler created with /sys/class/backlight/acpi_video0

Thank you for your reply.
I just tested it.
In the 390.xx driver witch is I can control brightness normally, the acpi_call can also control brightness by " …GFX0… ", and " …PEG0… " do nothing.
However, in the 535.xx driver witch is I cannot control brightness at all, the acpi_call cannot control brightness either. both " …GFX0… ", " …PEG0… " do nothing :(
Do you have any other suggestions that I can try?

Tried the 545 driver today. No luck and I also got the screen flickering/black screen issue with VRR enabled.

I also want to test the stable 550 drivers, but I can´t select the drivers from

ubuntu-drivers list

Do I have to wait or it it somehow possible to install the drivers manually without breaking the os?

You can use the graphics drivers ppa to get the latest driver for ubuntu.

Updated the drivers to 550 but also no luck. I will write the Linux Support Team again. Maybe they have some good news.

I want to give an update:

I switched to Debian 12 stable (KDE Plasma) and was able to install the latest Nvidia drivers. At the moment I am on 555.42.06 and it is possible now to set the brightness with FN+F8(-)/F9(+).

apt install linux-headers-amd64
sudo apt install software-properties-common -y
sudo add-apt-repository contrib non-free-firmware
curl -fSsL | sudo gpg --dearmor | sudo tee /usr/share/keyrings/nvidia-drivers.gpg > /dev/null 2>&1
echo ‘deb [signed-by=/usr/share/keyrings/nvidia-drivers.gpg] Index of /compute/cuda/repos/debian12/x86_64 /’ | sudo tee /etc/apt/sources.list.d/nvidia-drivers.list
sudo apt update
sudo apt install nvidia-driver nvidia-smi nvidia-settings

One solution found, another problem happened.

DLSS is not working. What am I missing?

Steam Startparameter: PROTON_ENABLE_NVAPI=1 %command%

Detected NVIDIA GPUs:
01:00.0 VGA compatible controller [0300]: NVIDIA Corporation TU104BM [GeForce RTX 2080 Mobile] [10de:1ed0] (rev a1)

Checking card: NVIDIA Corporation TU104BM [GeForce RTX 2080 Mobile] (rev a1)
Uh oh. Failed to identify your Debian suite.

| NVIDIA-SMI 555.42.06 Driver Version: 555.42.06 CUDA Version: N/A |
| GPU Name Persistence-M | Bus-Id Disp.A | Volatile Uncorr. ECC |
| Fan Temp Perf Pwr:Usage/Cap | Memory-Usage | GPU-Util Compute M. |
| | | MIG M. |

| 0 NVIDIA GeForce RTX 2080 On | 00000000:01:00.0 On | N/A |
| N/A 60C P8 9W / 150W | 434MiB / 8192MiB | 2% Default |
| | | N/A |

| Processes: |
| GPU GI CI PID Type Process name GPU Memory |
| ID ID Usage |
| 0 N/A N/A 897 G /usr/lib/xorg/Xorg 159MiB |
| 0 N/A N/A 1068 G /usr/bin/kwalletd5 2MiB |
| 0 N/A N/A 1170 G /usr/bin/ksmserver 50MiB |
| 0 N/A N/A 1172 G /usr/bin/kded5 2MiB |
| 0 N/A N/A 1173 G /usr/bin/kwin_x11 40MiB |
| 0 N/A N/A 1226 G /usr/bin/plasmashell 18MiB |
| 0 N/A N/A 1258 G …c/polkit-kde-authentication-agent-1 2MiB |
| 0 N/A N/A 1366 G …86_64-linux-gnu/libexec/kdeconnectd 2MiB |
| 0 N/A N/A 1373 G /usr/bin/kaccess 2MiB |
| 0 N/A N/A 1380 G …-linux-gnu/libexec/DiscoverNotifier 2MiB |
| 0 N/A N/A 1388 G /usr/bin/kalendarac 2MiB |
| 0 N/A N/A 1481 G …AAAAAAAACAAAAAAAAAA= --shared-files 2MiB |
| 0 N/A N/A 1490 G /usr/lib/firefox-esr/firefox-esr 119MiB |
| 0 N/A N/A 1496 G /usr/bin/konsole 2MiB |
| 0 N/A N/A 1571 G /usr/bin/kate 2MiB |
| 0 N/A N/A 1592 G …-gnu/libexec/xdg-desktop-portal-kde 2MiB |
| 0 N/A N/A 2236 G …local/share/Steam/ubuntu12_32/steam 2MiB |