NVIDIA GPU not turning off when using Manjaro on Optimus laptop

Support Graphics & Display
1

After a few years on vanilla Arch I gave Manjaro a try. So far so good and I’m pleased with the distro except for one thing.

On my previous Arch system I was able to get the NVIDIA driver to completely turn off my GPU when not in use (Laptop with Optimus) which was great for power consumption and generated heat and noise. All I had to do is follow that official NVIDIA guide.

However, now that I’m on Manjaro, the GPU only manages to reach a low power state (4W consumption) and turn off its memory but not the GPU entirely (I have an LED that tells me if the NVIDIA card is on or not).

Here is the output of cat /proc/driver/nvidia/gpus/0000:01:00.0/power:

Runtime D3 status:          Enabled (fine-grained)
Video Memory:               Off

GPU Hardware Support:
 Video Memory Self Refresh: Supported
 Video Memory Off:          Supported

which validates the GPU power management mode ( Option "NVreg_DynamicPowerManagement=0x02" is called fine-grained)

Calling nvidia-smi tells me that the only process is Xorg and that it’s doing nothing. The card is also not driving any display.

I tried a few kernels (5.6 to 5.8) and NVIDIA drivers 440 and 450 with no luck.

Does anyone experiences the same problem or have an idea on how to solve it?

2

You might want to check out optimus-manager which will allow you to “boot” your graphical interface with only one gpu (meaning you either use integrated or dedicated, but not both at the same time). This works for me (lenovo legion ntb) pretty well as I am either traveling (iGPU/intel) or sitting at home (dGPU/nvidia).

There is a lot of messy naming with dedicated GPU notebooks: prime, prime-offload, bumblebee, optimus, optimus-manager etc.

3

Thanks for the guides, I’ll take a look at them and let you know of the results

4

Hi!
Also take a look at optimus-switch, this option will you choose between cards but no using both at the same time. Other possibility is using tlp or slimbookbattery to disable all you want from the boot up

5

I really want to avoid logging out to switch between GPUs, especially since I know that the NVIDIA driver can power down the GPU by itself, which is much more flexible.

My only issue is getting this to work on Manjaro. I don’t get the different behavior compared to vanilla Arch…

I looked at @wereii guides but the first one seems to be to use only the NVIDIA GPU at anytime. The second one is about using optimus-manager, but I tried with and without this tool and the problem is the same.

6