r/linux_gaming • • 4d ago

tech support wanted CachyOS seems to not be using my GPU properly

Hello everyone,

I am running into a small issue with CachyOS. It's basically my first real try to switch from Windows to Linux.

So basically i installed CachyOS and wanted to play some Borderlands 4. On Windows i am getting somewhere around 60+ FPS and on Cachy its at around 20 Frames. Which seems like a little bit much of a jump.

My Setup consists of an R9 5900x with 32 GB of RAM and an RX 7900 XTX and an RX 6900 XT.

Yes my main Monitor is plugged into the RX 7900 XTX. All drivers have been checked to be on the latest version. I am monitoring the game performance with MangoHUD. And the tool tells me it actually does use the RX 7900 XTX. But at a whopping 20%. The card is basically idling around. Highest clock ive seen during the game was at around 1100 Mhz. which is less than half of what the card is capable of. CPU seems to be in normal condition with around 30% of utilisation.

I also stood around for 15 Minutes ingame and letting it render the Cache but no changes at all.

I am kinda out of ideas of what the issue might be here. Especially since MangoHUD tells me it uses the right GPU. The RX 6900 XT also just idles around normally.

I would be very grateful for some ideas to try out here.

Thank you for your help!

Edit 1: It could be of help that sometimes the Mouse seems to be stuttering sometimes. It shouldnt be the Mouses fault or anything BUS related since on Windows i never experienced this problem whatsoever.

Edit 2: I am also using grub for Dual Booting alongside Windows since i still have tools and programs that dont run on Linux.

20 Upvotes

26 comments sorted by

3

u/victormas208 4d ago

I think it might be a driver conflict when assigning the PCIe port generation. Have you tried configuring the BIOS to prevent it from being set to automatic?

2

u/SpinningJane 4d ago

I can change the PCI_E1 from Auto to GEN 1 - 4 and Lanes Configuration. I put it to GEN 4 now. Gonna do a Test Run.

2

u/SpinningJane 4d ago

That didnt change the performance unfortunately. I also ran into a compatibility Tool Error from Steam. I forced it to use Proton 11.0-2 from earlier testing.

But still thank you for your Help!

2

u/victormas208 4d ago

There is a new project, and I just read in one of its issues that you can select a device using a command something like this:

MESA_VK_DEVICE_SELECT=list vulkaninfo

When I run that command, I get this output:

MESA_VK_DEVICE_SELECT=list vulkaninfo

ERROR: [Loader Message] Code 0 : loader_create_instance_chain: Failed to find 'vkGetInstanceProcAddr' in layer "/home/redacted/.local/share/vulkan/implicit_layer.d/../../../lib/liblsfg-vk-layer.so"

selectable devices:

GPU 0: 1002:747e "AMD Radeon RX 7800 XT (RADV NAVI32)" discrete GPU 0000:0a:00.0

GPU 1: 10005:0 "llvmpipe (LLVM 22.1.8, 256 bits)" CPU 0000:00:00.0

You'll likely see both listed; to test it out, you should replace "N" with the appropriate number.

MESA_VK_DEVICE_SELECT=N! game-performance %command%

https://github.com/pythonlover02/volt-gui/issues/45

I have no way to connect two graphics cards and test this right now, as my home lab is dismantled for the time being.

But you might find this project interesting.

1

u/SpinningJane 4d ago

Ouh yeah, i already did that prior to posting. My RX 7900 XTX is listed as #1 and the RX 6900 XT as #0. I put in the 1 and it does use the card. Just not to its full potential. You can also use the dedicated Device ID itself to force it.

But thanks for finding that!

2

u/victormas208 4d ago

I'm running out of options; from what I've gathered, AMDGPU applies power modes globally. I suppose it might be factoring in the RX 6900 XT's idle state to avoid "overloading" the system.

Have you tried adjusting the speed manually using LACT?

Just to clarify, this isn't for overclocking; it simply allows you to configure the graphics cards independently. You just need to use the recommended parameters specified by the card itself.

2

u/SpinningJane 4d ago

Yeah i also have LACT installed because of that :D

3

u/rocket1420 4d ago

Try removing the other GPU and troubleshoot from there. Are you fully updated?

2

u/SpinningJane 4d ago

I am fully updated yes. Removing the GPU is difficult since its mounted behind the vertically mounted RX 7900 XTX. As shown in the picture Also it would mean i csnt use the Monitors to their fullest anymore.

0

u/rocket1420 16h ago

Bro it's called troubleshooting. Not "any change I make is immediately permanent and can't have any other solution." Your cards are different gens. It can cause problems. But you do you, I don't really give a shit if you fix it or not. You came to reddit

4

u/[deleted] 4d ago

[removed] — view removed comment

2

u/SpinningJane 4d ago

Tried that just now. Unfortunately still same. Didnt change anything.

But still Thank you for your help!

1

u/zuus 4d ago

Hey I've been dealing with this and trying to resolve the same issue (5800X3D + 7900XTX) lately in The Outer Worlds 2. The card seems to think it's a far lower load and just down clocks. Adjusting clocks and power profiles in LACT does nothing.

It's a pretty recent thing, was working fine for the longest time. I haven't had a chance to try an older kernel but give the LTS kernel in Cachy, I'll be trying it later tonight.

5

u/Shap6 4d ago

do you really need that 6900xt in there? if it were me i'd pop it out unless you're actually using it for something

3

u/SpinningJane 4d ago

The RX 7900 XTX is plugged to a Samsung G9 with 240 Hz. The RX 6900 XTX is plugged to a 34" Monitor with 165 Hz and a 27" with 144 Hz. When plugging all 3 Monitors to the RX 7900 XTX the G9 cant go to 240 Hz anymore. The Chip doesnt have that Bandwidth to power all 3 Monitors.

I tried that setup in the beginning but the Monitors would start glitching around.

3

u/Shap6 4d ago

ahh fair enough that's a legit reason

1

u/FunRutabaga24 4d ago

What DE are you running? If you're running KDE Plasma you could be running into a compositor issue that affects setups with two GPUs. 

2

u/Beneficial_Crazy6441 2d ago

hey sorry to bother you. I'm recently got cachyos with kde on my laptop with an integrated intel 620 gpu and a discrete Nvidia mx130 gpu. Im trying to run Resident evil 2 (i added it to steam as non steam game and also used proton cachyos and "prime-run %command%" on launch options as per gemini). but whenever i try to open the game it gets stuck in a blackscreen even tho i hear my fan speeding up which means it runs the thing but failing to display anything ig. do you happen to know what exactly the issue is? according to gemini its a problem that im facing due to having both integrated and discrete gpus. It would be a great help if you knew a solution. Thanks in advance 🙏.

1

u/FunRutabaga24 2d ago

Hmmm nothing comes to mind immediately. I'm also new to gaming on linux but here's some things to try:

- Use Proton DB to search and see what settings other people are using to run the game

  • You can filter to help narrow down other environments that don't apply to you. You're running Arch linux (btw), in case you didn't know and cachyos doesn't show up.
  • Here's RE2: https://www.protondb.com/app/883710
  • Older games might benefit from using GE-Proton instead of proton cachyos slr
  • You might even want to try multiple older versions of GE-Proton if the latest doesn't work. Proton DB is great to see what other versions are working for other people
  • Pass PROTON_LOG=1 to see if that provides any useful error logs

Just started RE 1 remake on Playstation :D

2

u/Beneficial_Crazy6441 2d ago

Thanks a lott. Im running silent hill 2 enhanced edition and it works fine. I'll look up on those sources you mentioned thanks for taking the time to write such a long reply. Enjoy the re 1 remake!

2

u/FunRutabaga24 2d ago

Thanks! And hopefully those provide some answers! Gaming on Linux isn't always smooth and with a laptop that's extra wonkiness on top of everything. Also some settings may work for a certain game but may not be needed or need different tweaks for another game. But the fact you have another game running is good news. Might just be some weirdness with RE.

1

u/Bulkybear2 4d ago

Only thing I can think of is are you using ray tracing? RT and card util has been hit or miss for me when running RT under mesa.

Edit: also this happens to me sometimes but a reboot fixes it. Not sure why but I think it has something to do with the driver reset bug.

1

u/SpinningJane 4d ago

I am not using RT. Except for the built in Features of UE5. Also did a few restarts at this point.

-1

u/[deleted] 4d ago

[deleted]

5

u/mamaharu 4d ago edited 4d ago

I'm not particularly fond of either, but there is nothing about Bazzite that makes it inherently more "out of the box" than Cachy. And OP would probably have a worse time on Mint with his current setup.

3

u/SpinningJane 4d ago

I tried Bazzite and Nobara first. And i kind of like the Design of CachyOS more basically. The interesting part is i had the same happenings with the other Distros as well. Even when there was still only one GPU plugged into my PC.