nixos-hardware

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Looking through the repository, none of the configurations have hardware.nvidia.powerManagement configured. On my dell machine, I've been able several watts with;

  hardware.nvidia = {
    powerManagement = { 
      enable = true;
      finegrained = true;
    };
    nvidiaPersistenced = true;
  };

These options control these things from the arch wiki: https://wiki.archlinux.org/title/PRIME#PCI-Express_Runtime_D3_(RTD3)_Power_Management

I'm wondering if not including this configuration is intentional or not? I'm not sure if this counts as an opinionated setting. If it is okay I would like to submit a pr for my machine.

I don't think this is intentional, at least I am not aware of that. Could be added here? https://github.com/NixOS/nixos-hardware/blob/2a7063461c3751d83869a2a0a8ebc59e34bec5b2/common/gpu/nvidia.nix#L19

From reading the nvidia docs it seems there is less to configure that I thought. The configuration is dependent on the microarchitecture. For cards earlier than turing (below 20 series) there is no power saving and the configuration should be:

  hardware.nvidia = {
    powerManagement = { 
      enable = true;
    };
  };

For turing (20 series) cards it should be:

  hardware.nvidia = {
   powerManagement = { 
     enable = true;
     finegrained = true;
   };
   nvidiaPersistenced = true;
 };

and for ampere (30 series) and later cards power saving is enabled by default so it is just:

  hardware.nvidia = {
    powerManagement = { 
      enable = true;
    };
  };

I'm not 100% sure on this and I only have my laptop to test but I think they are right. So maybe its best set hardware.nvidia.powerManagement.enable = true; is in https://github.com/NixOS/nixos-hardware/blob/2a7063461c3751d83869a2a0a8ebc59e34bec5b2/common/gpu/nvidia.nix#L19 and for laptops with turing cards we can enable the other things in their configuration?

There could be a subprofile for turing cards that is more specific. Do you have a turing card?

Yeah I do.

Should I submit a pr with another file in the gpu folder with the turing configuration and add the enable the powerManagement option in the nvidia file?