
With the new Radeon 9070 XT the came will crash after a few seconds of playing
With my Radeon 6600 the game runs perfectly. With the 9070 XT main menu works fine, running the game internal benchmark works fine. Issue occurs when you start playing after a few seconds of play, will lock the entire computer and need to reboot.
Works great out of the box, including DLCs and even mods

-NoStartupMovies -NoLauncher
GPU accelerated PhysX is not available, lots of freezes for example when lootsplosions happen.
The only issue is most random players don't have manners.
Given my hardware is pretty low-mid grade i had to turn down the graphics settings to low, But, its pretty much always worked well.

mangohud %command%
BL3 Settings: Windowed Borderless (2560 x 1600), DX12, Vsync off, Render Res 50%, Cap 60, FOV 90, Medium Quality
HHD: TDP 20W + Boost, CPU Auto, GPU Auto
Bios: Vram Auto, CPU 6, Ram Speed 6400

after an hour of playing game starts to stutter like hell
After first launch game freezes while loading on start on claptrap loading scene, to fix it you need to delete files in directory: Steam/steamapps/compatdata/397540/pfx/drive_c/users/steamuser/AppData/Local/Borderlands 3/Saved/ you need to delete these files before every launch
Singleplayer works fine. Will try co-op when I have friends

Flawless by default.
You can't ask for a smoother experience. I'm playing at 4k 60 fps, with all graphical settings maxed out, and consistently maintaining a stutter-free 60 fps or better framerate. This is a shining example of Proton's success!

on ultra settings a bit of frame rate drops
runs good out of the box ultra settings a bit of fps drops on high settings no issues.

Гра працює чудово
Запускати на версії Протона 9.0-4 або новіших. На старіших його версіях не працюють відео-вставки, типу "хмаринки телепатичного зв'язку".
gamemoderun %command% -NoStartupMovies -NoSplash -notexturestreaming -dx12
I did have only one crash, while playing co-op a friend.

-NoStartupMovies -nosplash
Current Steam Beta will cause the game and itself to crash. Opt out of the beta program to avoid those problems.

Clicking play, the game does not boot.
gamemoderun %command% -nostartupmovies -nosplash
Switches to "launching" then causes Steam to completely crash. Previously was working without issue for 50-ish hours of game time.
Literally unplayable, the game runs fine for a few minutes like 120 fps then starts a stutter powerpoint slide show.

I had a moment where the sound (of gunshots, dialogues) was muffled. Only restarting the game completely solved it (quit and loading hadn't solved it).
Stutterings. Nothing too frequent and it didn't bother me during the game.
Subtitles. There are times when the subtitles do not appear or the text that appears refers to a previous audio.
Played with Proton-Experimental [bleeding-edge] in Custom settings (most options on Low, but mainly Texture Streaming on Ultra), 1080p windowed fullscreen with 60 FPS.
Some reporters recommend using -notexturestreaming
instead of setting the Texture Streaming on Ultra. I tried, but it made the performance much worse.
Also, I didn't notice any major differences between DX11 (dxvk) and DX12 (vkd3d). But in DX12, the game takes longer to load. I preferred to play with DX11.
Amazing looter shooter game and runs realy great!

minor flickering
Out of the box !

Runs perfectly except for some very occasional crashes.
Occasional crashing. Happens maybe once every 5 hours or so. Seems to be a problem on Windows as well but more frequent under Proton.
Using DX12 instead of DX11 seems to run better, at least on my system.
To do this. go to .../compatdata/397540/pfx/drive_c/users/steamuser/Documents/My Games/Borderlands 3/Saved/Config/WindowsNoEditor/
.
Edit GameUserSettings.ini
. Set PreferredGraphicsAPI
to DX12
.

-nostartupmovies -nosplash
runs out of the box, just, make sure to not use windowed borderless as it causes the game to lag

Graphic details on Ultra everything worked well
game-performance %command% -nostartupmovies -nosplash -dx12

Had some performance problems in borderless window mode, but runs great in fullscreen.
error message in terminal FileNotFoundError: [Errno 2] No such file or directory: '/mnt/gamedisk/steamapps/compatdata/397540/tracked_files' after creating the file "touch tracked_files" the game launched without issue.

If you are using an external monitor it is fine but it is hard to read on the deck itself.
Sometimes the textures took a little longer to load but it loads the textures but it wasn't super noticeable.

%command% -nostartupmovies -nosplash
Using Proton Experimental and the default an OpenGL renderer wayland window would open that I couldn't close. GE-Proton9-13 resolved this. Didn't actually negatively affect anything in game though.

Works fine without tinkering for me
Works OOTB for me. I played coop with a friend that runs Windows and has the game on a different launcher (not steam), works fine too (you have to activate Crossplay in the Ingameoptions for that).
screen stalling and lag in borderless window mode
prime-run %command%

Crashes instantly on DX11. Launches on DX12 and can hear the game, but not see it.
-DXVK_FILTER_DEVICE_NAME="Intel(R)" -nostartupmovies -nosplash -notexturestreaming -dx12
DX11 error message:
LowLevelFatalError [File:Unknown] [Line: 252] D3DRHI->GetFactory()->CreateSwapChain(DXGIDevice, &SwapChainDesc, SwapChain.GetInitReference()) failed at D:\Oak\main\Engine\Source\Runtime\Windows\D3D11RHI\Private\Windows\WindowsD3D11Viewport.cpp:156 with error E_FAIL
0x00006fffffc1cf07 kernelbase.dll!UnknownFunction [] 0x00000001416a6864 Borderlands3.exe!UnknownFunction [] 0x000000014167695c Borderlands3.exe!UnknownFunction [] 0x0000000141621dad Borderlands3.exe!UnknownFunction [] 0x0000000141a44939 Borderlands3.exe!UnknownFunction [] 0x0000000141a23dd6 Borderlands3.exe!UnknownFunction [] 0x0000000141a3ac3c Borderlands3.exe!UnknownFunction [] 0x00000001420a8c3e Borderlands3.exe!UnknownFunction [] 0x00000001420bf875 Borderlands3.exe!UnknownFunction [] 0x000000014185bdb1 Borderlands3.exe!UnknownFunction [] 0x0000000142449591 Borderlands3.exe!UnknownFunction [] 0x0000000142011cd3 Borderlands3.exe!UnknownFunction [] 0x000000014044332f Borderlands3.exe!UnknownFunction [] 0x000000014043c75c Borderlands3.exe!UnknownFunction [] 0x000000014043c98a Borderlands3.exe!UnknownFunction [] 0x00000001404460a9 Borderlands3.exe!UnknownFunction [] 0x0000000143ddc6ee Borderlands3.exe!UnknownFunction [] 0x00006fffffed482d kernel32.dll!UnknownFunction []

WINEDLLOVERRIDES="d3d11.dll=n,b" %command% -nostartupmovies -nosplash -notexturestreaming
Launch options are for running mods (which all work) and skipping the annoying intros + improving performance.
gamemoderun mangohud %command% -NoStartupMovies -NoSplash
The game does stutter a small bit when loading new areas, but otherwise is fine

Game wouldn't launch when installed to an EXT4 formatted mechanical hard drive. When I moved it to a BTRFS formatted NVME, it launched fine.
Aside from the weird issue of not booting from an EXT4 file system, worked fine.

-NoStartupMovies
Fixed the performance problems by uninstalling the built-in amdvlk driver, and downloading the vulkan-radeon driver.
The performance issues before I changed vulkan drivers could just be a thing with my computer. But if it isn't, I highly recommend trying another vulkan driver if you have AMD.

Runs better than on Windows! NTFS drives wont work! Recommend installing on BTRFS drive!
gamemoderun DXVK_ASYNC=1 VKD3D_CONFIG=dxr,dxr11 PROTON_ENABLE_NGX_UPDATER=1 %command% -nosplash -notexturestreaming
Use BTRFS and you should be fine

55-60 FPS on low settings with amd fideltiy sharpening on, medium 47-50fps fsr on, high 27-30 fps fsr on.
gamemoderun mangohud %command%
I would run it the low settings preset, then turn on amd fidelity sharepning option on the bottom in the visuals menu, and then up some two settings up by one (low to medium) and you'll get a solid 55-60fps still. Game runs great out of the box using ProtonGE 9-11, no launch options technically required. It works great on the steam deck. I haven't tested normal proton experimental / proton 9 but they most likely work out of the box as well. Great game for linux pc users or linux steam deck users

Works out of the box with or without launch options. Really good performance/fps with rtx 4070 & i7 14700k
gamemoderun PROTON_HIDE_NVIDIA_GPU=0 PROTON_ENABLE_NVAPI=1 DXVK_ASYNC=1 VKD3D_CONFIG=dxr,dxr11 PROTON_ENABLE_NGX_UPDATER=1 mangohud %command% -nostartupmovies -nosplash
I had to set FPS limit to 120 because my screen would flicker on Ultra/"Badass" settings listed in the menu. I am going to try to raise it to 165 since that's my monitors refresh rate, and I'm guessing it will work. But, if it doesn't just set the fps limit to 120 and you can use the maxed out settings just fine. I get very high fps in this game even at the highest settings with my system. I haven't noticed any glitches or any other problems and I doubt I will other then the one I just mentioned which was easy to fix. On my steam deck, it also works flawlessly without any launch options and good fps/performance. Great game!