Arch Linux

SofieSasao

Member

Registered: 2024-03-03

Posts: 9

Screen brightness is very low and not adjustable

I have a laptop (HP Victus 15-fa1000) with dual boot.

I recently installed Arch on it and ever since then screen brightness level is really low in Grub menu and Arch itself. Also, my Arch (i3) does not support control of brightness using special keys (Fn+F2, Fn+F3) at the moment.
I also experience the same problem on any live USB system or installation medium. The other system on the laptop is Windows 11, but I have never had this issue on it.

There are nvidia proprietary drivers installed on the system, and early KMS start is set up in case this is important.

To make brightness  adjustable I have tried adding kernel parameter and xorg.conf option as suggested on this wiki page (but xorg.conf file no longer exist on my system).

nvidia.NVreg_RegistryDwords=EnableBrightnessControl=1

Option "RegistryDwords" "EnableBrightnessControl=1"

As for the nvidia-bl-dkms package - I did not try it yet, because I still don't fully understand this and don't want to accidentally make unnecessary and potentially breaking change.
I also added another kernel parameter from the first method in this guide, which also didn't seem to work.

acpi_backlight=vendor

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 21,809

Re: Screen brightness is very low and not adjustable

As we've learned in the previous topic, the nvidia card is not driving your laptop display. You can stop any attempts of fixing this via nvidia. Drop the acpi_backlight parameter. i3 does not have any built-in mechanism that would control this as is, what are you trying to use here? I suggest setup acpilight and add your user to the video group and then relog and then see what happens running the appropriate acpilight commands (which you can then keybind from i3)

SofieSasao

Member

Registered: 2024-03-03

Posts: 9

Re: Screen brightness is very low and not adjustable

Thank you for your reply!

You can stop any attempts of fixing this via nvidia.

Sure, I just wanted to be clear on what I tried to address this problem earlier.

i3 does not have any built-in mechanism that would control this as is, what are you trying to use here?

I didn't mean that I expect i3 to control brightness. I meant I didn't set it up yet. Sorry for the confusion.
xbacklight commands didn't actually work though.

Drop the acpi_backlight parameter.

I suggest setup acpilight and add your user to the video group and then relog and then see what happens running the appropriate acpilight commands (which you can then keybind from i3)

I did it, and I got brightness control working inside Arch, thank you!
For those who also have similar issue, please, take a look at these resources:
https://wiki.archlinux.org/title/Backli … ess_change
https://gitlab.com/wavexx/acpilight
These i3 bindings worked for me:

bindsym XF86MonBrightnessUp   exec xbacklight -inc 2
bindsym XF86MonBrightnessDown exec xbacklight -dec 2

Unfortunately, this didn't solve brightness issue in the Grub menu and at the beginning of the Plymouth animation (until partition is decrypted). All information in this regard that I found suggests to add acpi_backlight and acpi_osi kernel parameters. I understand that it doesn't work for me, so I'm kind of lost here.

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 21,809

Re: Screen brightness is very low and not adjustable

I doubt you can fix things that early in the chain without there being a lower/UEFI/BIOS level option for GRUB at least. acp_backlight parameter is pretty much deprecated and it's not going to magic something before the kernel actually runs anyway.