How to choose specific gpu? Optimus setup

Ask Fedora
,
1

Hello, I have a laptop with 2 GPU’s when I run switcherooctl I get:

Device: 0
Name: Intel® UHD Graphics 620
Default: yes
Discrete: no
Environment: DRI_PRIME=pci-0000_00_02_0 VK_LOADER_DRIVERS_SELECT=*intel*

Device: 1
Name: NVIDIA Corporation GP108M [GeForce MX150]
Default: no
Discrete: yes
Environment: DRI_PRIME=pci-0000_3b_00_0

How do I choose the nvidia one to run ? Or is it not that simple? Does the nvidia start when the load is high?

2

Or is the nvidia gpu already in use just that I don’t see it? I am very un-experienced with fedora. Are both the gpus in use with optinus?

3

I added Optimus setup to the so you are more likely to get a reply.

5

The way it is supposed to work is to switheroo to the fgpu when the load is high.

Use some kind of gpu monitoring software to see if it does, I checked btop and that has a gpu section, but I dont have dual gpu, so try it out.

6

Fgpu?

7

The eff key is next to the dee key, so common typo. Where is AI when you need it?

8

oh ok

9

Fedora GPU :1st_place_medal:

Yea, typo. dgpu.

10

I’m in btop now, do I try running plenty of stuff to increase load to see if it switches? Otherwise currently only the integrated gpu is shown

11

Maybe btop is not the right tool, but otherwise yes, jack up the juice.

Here is a thread that might give some insight, but I have not confirmed it (as I don’t have dual gpu, or any Nvidia for that matter). ⚙️ Dual GPU Setup on Fedora: NVIDIA + Intel (Optimus) with Offloading - DEV Community

12

Sorry for asking so many questions, but in the article when offloading
is mentioned does that mean that for example an app instead of using the intel(default gpu) it uses the nvidia?

13

Yes, that is correct.

Feel free to ask as many questions as you want.

14

The user can also use switcherooctl to select the GPU for a specific app when launched. See man switcherooctl which gives the instructions.

       launch [OPTION] COMMAND...
           Launch COMMAND on a specific GPU. If no GPU are specified the first discrete (non-default) GPU is used, or the default GPU if there's no discrete GPU.

           Options

               -g --gpu=GPU
                   The GPU to launch on. The GPU identifier can be gathered using the list command.
15

Do you know a way to put load on a gpu in a controlled way?

16

Are you asking
Can one assign an application to use a specific gpu, and limit the power consumption of said gpu to e.g. 50% ?

If so, I don’t know but someone here may.

17

Hi Koli,
You might try nvtop to get a better picture of what is going on … also .. do you have the Nvidia drivers installed?
For a stress testing tool, try FurMark from flathub …

18

Yes I do