I'm on EndeavourOS with an Nvidia gpu. I've not had to do anything extra for the the version of proton that comes with steam to work besides install the os with the Nvidia proprietary drivers. And then running eos-update --aur --nvidia

I did notice that I got a lot of screen tearing if using Wayland and that more recent versions of proton didn't work if either Force Composition Pipeline or Force Full Composition Pipeline were enabled; which should have fixed the screentearing so I just use x11 for now.

There are some things I did to make my experience better however. Like installing an proton-ge. Here is a list of what I installed.

nvidia-dkms
nvidia-settings
libva-nvidia-driver # required by vlc to play mkv files with nvidia gpu
nvidia-tweaks # https://github.com/ventureoo/nvidia-tweaks
lib32-nvidia-utils
gamemode
proton-ge-custom-bin
lib32-libudev0-shim # fixes Steam runtime's super old 32 bit version of libnm
lib32-libnm # required if using systemd 253.5-2 or newer

I would also install nvidia-dracut-hook if you are using both Nvidia and dracut. Dracut is the default on recent versions on endeavorOS.

For proton ge, I also added myself to the games group with

sudo usermod $USER -a -G games

I also like to prepend the following to my games launch options in steam

gamemoderun PROTON\_CONFIG=dxr11,dxr PROTON\_ENABLE\_NVAPI=1 PROTON\_HIDE\_NVIDIA\_GPU=0 VK\_ICD\_FILENAMES=/usr/share/vulkan/icd.d/nvidia\_icd.json VKD3D\_CONFIG=dxr11,dxr VKD3D\_DISABLE\_EXTENSIONS=VK\_KHR\_present\_id,VK\_KHR\_present\_wait VKD3D\_FEATURE\_LEVEL=12\_1 VKD3D\_SHADER\_MODEL=6\_6

And I set proton-ge as my default proton version on the steam options.