NVIDIA: Difference between revisions
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This page attempts to cover everything related to the use of NVIDIA GPUs on NixOS. | |||
== Enabling == | |||
=== Kernel modules from NVIDIA === | |||
Kernel modules from NVIDIA offer better performance than other alternatives, but make the system unfree by requiring proprietary userspace libraries that can interface with the kernel modules. Users that want to have a fully free and open-source system should use [[NVIDIA#Nouveau|Nouveau]] instead. | |||
To enable them, add <code>"nvidia"</code> to the list of enabled video drivers defined by the <code>services.xserver.videoDrivers</code> option. | |||
{{Note|<code>hardware.graphics.enable</code> was named <code>hardware.opengl.enable</code> '''until NixOS 24.11'''.}} | |||
{{Note|Since driver version 560, you also will need to decide whether to use the open-source or proprietary modules by setting the <code>hardware.nvidia.open</code> option to either <code>true</code> or <code>false</code> respectively.<br><br>Open-source kernel modules are preferred over and planned to steadily replace proprietary modules<ref>https://developer.nvidia.com/blog/nvidia-transitions-fully-towards-open-source-gpu-kernel-modules/</ref>, although they only support GPUs of the Turing architecture or newer (from GeForce RTX 20 series and GeForce GTX 16 series onwards). Data center GPUs starting from Grace Hopper or Blackwall must use open-source modules — proprietary modules are no longer supported.<br><br>''If you're using proprietary modules'', make sure to allow [[Unfree software|unfree software]]. The unfree NVIDIA packages include <code>nvidia-x11</code>, <code>nvidia-settings</code>, and <code>nvidia-persistenced</code>. | |||
}}{{Warning|If you use a laptop with both dedicated and integrated GPUs, remember to [[#Hybrid_graphics_with_PRIME|configure PRIME]] in order to make your dedicated NVIDIA GPU work properly with your integrated GPU. Your configuration '''might not work''' if you skip this step.}}{{file|configuration.nix|nix|<nowiki> | |||
{ | |||
hardware.graphics.enable = true; | |||
services.xserver.videoDrivers = [ "nvidia" ]; | |||
hardware.nvidia.open = true; # Set to false for proprietary drivers | |||
} | |||
</nowiki>}} | |||
==== Legacy branches ==== | |||
GPUs of the Kepler architecture or older (most GeForce 600/700/800M cards and older) are no longer supported by latest proprietary modules. Instead, users of these GPUs must use legacy branches that may still receive updates, as long as the GPUs themselves remain supported by NVIDIA. You can find which legacy branch you need to use by searching for your GPU model on [https://www.nvidia.com/en-us/drivers/unix/legacy-gpu/ NVIDIA's official legacy driver support list]. | |||
= | To use legacy branches, you need to set the <code>hardware.nvidia.package</code> option to a package set named <code>config.boot.kernelPackages.nvidiaPackages.legacy_<branch></code>.{{file|configuration.nix|nix|<nowiki> | ||
{ config, ... }: # ← Required to get the packages used by the currently configured kernel, including drivers | |||
{ | |||
# Last version that supports Kepler GPUs | |||
hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.legacy_470; | |||
} | |||
</nowiki>}}Nixpkgs does not endeavor to support all legacy branches since older, unmaintained legacy branches can become incompatible with newer kernel and X server versions, and at some point it becomes infeasible to patch them to cooperate with modern software. You can find the list of supported legacy branches under [https://github.com/NixOS/nixpkgs/blob/master/pkgs/os-specific/linux/nvidia-x11/default.nix in the Nixpkgs repository]. | |||
==== Beta/production branches ==== | |||
By default, modules from the stable branch are used, which come from latest release available for the current architecture — while x86-64 and aarch64 systems follow the "New Feature Branch" releases as they remain actively developed, 32-bit x86 and ARM systems remain on the 390.xx branch as that is the last branch with 32-bit support. | |||
Instead of the stable branch, users can also switch to the beta branch, which has more new features and experimental changes at the risk of containing more bugs, or the production branch, a more conservative, well-tested stable version that is suitable for production use with minimum breakage, at the cost of being behind in terms of new features. | |||
Using the beta and production branches are similar to how one would use legacy branches:{{file|configuration.nix|nix|<nowiki> | |||
{ config, ... }: | |||
{ | |||
#hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.stable; # Default | |||
hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.beta; | |||
hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.production; | |||
} | |||
</nowiki>}} | |||
=== Nouveau === | |||
Nouveau is a set of free and open-source drivers for NVIDIA GPUs that provide 2D/3D acceleration for all NVIDIA GPUs. Its use is in general not recommended due to its considerably worse performance compared to NVIDIA's kernel modules, as it does not support reclocking (changing the GPU clock frequency on-demand) for many NVIDIA GPUs<ref>https://www.phoronix.com/forums/forum/linux-graphics-x-org-drivers/open-source-nvidia-linux-nouveau/998310-nouveau-persevered-in-2017-for-open-source-nvidia-but-2018-could-be-much-better#post998316</ref>. Nevertheless it remains a viable option for users who want a fully free and open-source operating system as it does not contain any proprietary components, unlike NVIDIA's kernel modules and userspace libraries. | |||
{{file| | Nouveau is enabled by default whenever graphics are enabled, and does not need any extra configuration.{{file|configuration.nix|nix|<nowiki> | ||
{ | { | ||
hardware.graphics.enable = true; | hardware.graphics.enable = true; | ||
} | } | ||
</nowiki>}} | </nowiki>}} | ||
== | == Configuring == | ||
=== Power management === | |||
=== Hybrid graphics with PRIME === | |||
Laptops often feature both an integrated GPU (iGPU) and a dedicated GPU (dGPU) in order to strive a balance between performance and power consumption — while the dGPU is used for performance-intensive tasks such as gaming, video editing, 3D rendering, compute jobs, etc., the iGPU can be used to render common 2D elements like application windows and the desktop environment. | |||
PRIME, therefore, is a technology developed to facilitate the cooperation between the two GPUs and is critical for the laptop's graphical performance. Depending on your needs, you can configure PRIME in one of three modes, which have different tradeoffs in terms of performance and battery life. | |||
==== Common setup ==== | |||
All PRIME configurations require setting the PCI bus IDs of the two GPUs. One easy way to do find their IDs is by running <code>lspci</code> from the <code>pciutils</code> package, and then finding devices that are classified as VGA controllers. After double checking that the listed devices are indeed your integrated and dedicated GPUs, you can then find the PCI IDs at the beginning of each line. Exact results may vary, but an example output might look like:<syntaxhighlight lang="console"> | |||
$ nix shell nixpkgs#pciutils -c "lspci" | grep "VGA" | |||
0000:00:02.0 VGA compatible controller: Intel Corporation TigerLake-H GT1 [UHD Graphics] (rev 01) | |||
0000:01:00.0 VGA compatible controller: NVIDIA Corporation GA106M [GeForce RTX 3060 Mobile / Max-Q] (rev a1) | |||
</syntaxhighlight>Before putting them into your configuration, however, '''they must first be reformatted''' — take the last three numbers, convert them from hexadecimal to decimal, remove the leading zeroes, concatenate them with colons, and then add a <code>PCI:</code> prefix. Then, they can be set under <code>intelBusId</code>, <code>nvidiaBusId</code>, or <code>amdgpuBusId</code> in <code>hardware.nvidia.prime</code>, depending on the manufacturer of the GPU:{{file|configuration.nix|nix|<nowiki> | |||
<syntaxhighlight lang=" | |||
</syntaxhighlight> | |||
{ | { | ||
hardware.nvidia.prime = { | |||
intelBusId = "PCI:0:2:0"; | |||
nvidiaBusId = "PCI:1:0:0"; | |||
#amdgpuBusId = "PCI:54:0:0"; # If you have an AMD iGPU | |||
}; | |||
} | } | ||
</nowiki>}} | </nowiki>}} | ||
==== Offload mode ==== | ==== Offload mode ==== | ||
{{Note|Offload mode is available '''since NixOS 20.09 and NVIDIA driver version 435.21''', and requires an NVIDIA GPU of the Turing generation, or newer and a compatible CPU — either an Intel CPU from the Coffee Lake generation or newer, or an AMD Ryzen. Offload mode is '''incompatible''' with sync mode.}} | |||
Offload mode puts your dGPU to sleep and lets the iGPU handle all tasks, except if you call the dGPU specifically by "offloading" an application to it. For example, you can run your laptop normally and it will use the energy-efficient iGPU all day, and then you can offload a game from Steam onto the dGPU to make the dGPU run that game only. For many, this is the most desirable option. | |||
To enable offload mode, set the <code>hardware.nvidia.prime.offload.enable</code> option to <code>true</code>: | |||
{{file|configuration.nix|nix|<nowiki> | |||
{ | |||
hardware.nvidia.prime = { | |||
offload.enable = true; | |||
{{file|nvidia-offload|bash|<nowiki> | |||
intelBusId = "PCI:0:2:0"; | |||
nvidiaBusId = "PCI:1:0:0"; | |||
#amdgpuBusId = "PCI:54:0:0"; # If you have an AMD iGPU | |||
}; | |||
} | |||
</nowiki>}}When you want to run a program on the dGPU, you only need to set a few environment variables for the driver to recognize that offload mode should be used. If <code>hardware.nvidia.prime.offload.enableOffloadCmd</code> is set to true, NixOS will generate a wrapper script named <code>nvidia-offload</code> that sets the right variables for you:{{file|nvidia-offload|bash|<nowiki> | |||
export __NV_PRIME_RENDER_OFFLOAD=1 | export __NV_PRIME_RENDER_OFFLOAD=1 | ||
export __NV_PRIME_RENDER_OFFLOAD_PROVIDER=NVIDIA-G0 | export __NV_PRIME_RENDER_OFFLOAD_PROVIDER=NVIDIA-G0 | ||
Line 170: | Line 99: | ||
export __VK_LAYER_NV_optimus=NVIDIA_only | export __VK_LAYER_NV_optimus=NVIDIA_only | ||
exec "$@" | exec "$@" | ||
</nowiki>}} | </nowiki>}}If everything is configured correctly, then running a program like <code>glxgears</code> should use the iGPU, while running <code>nvidia-offload glxgears</code> should only use the dGPU. | ||
==== Sync mode ==== | ==== Sync mode ==== | ||
{{Note|Sync mode is available '''since NixOS 19.03 and NVIDIA driver version 390.67''', and is '''incompatible''' with both offload and reverse sync modes. Sync mode also requires using a desktop manager that respects the <code>services.xserver.displayManager.setupCommands</code> option, including LightDM, GDM and SDDM.}}In sync mode, rendering is completely delegated to the dGPU, while the iGPU only displays the rendered framebuffers copied from the dGPU. Sync mode offers better performance and greatly reduces screen tearing, at the expense of higher power consumption since the dGPU will not go to sleep when not needed, as is the case in offload mode. Sync mode may also solve some issues with connecting a display in clamshell mode directly to the GPU. | |||
To enable sync mode, set the <code>hardware.nvidia.prime.sync.enable</code> option to <code>true</code>: | |||
{{file|/etc/nixos/configuration.nix|nix|<nowiki> | {{file|/etc/nixos/configuration.nix|nix|<nowiki> | ||
Line 199: | Line 110: | ||
hardware.nvidia.prime = { | hardware.nvidia.prime = { | ||
sync.enable = true; | sync.enable = true; | ||
intelBusId = "PCI:0:2:0"; | intelBusId = "PCI:0:2:0"; | ||
# amdgpuBusId = "PCI:54:0:0"; | nvidiaBusId = "PCI:1:0:0"; | ||
#amdgpuBusId = "PCI:54:0:0"; # If you have an AMD iGPU | |||
}; | }; | ||
} | } | ||
</nowiki>}} | </nowiki>}} | ||
==== Reverse sync mode | ==== Reverse sync mode ==== | ||
{{Note|Reverse sync mode is available '''since NixOS 23.05 and NVIDIA driver version 460.39''' and is still an experimental, buggy feature<ref>https://forums.developer.nvidia.com/t/the-all-new-outputsink-feature-aka-reverse-prime/129828/67</ref>. '''Your mileage may vary.''' Reverse sync mode is '''incompatible''' with sync mode and requires using a desktop manager that respects the <code>services.xserver.displayManager.setupCommands</code> option, including LightDM, GDM and SDDM.}}The difference between regular sync mode and reverse sync mode is that the '''dGPU''' is configured as the primary output device, allowing displaying to external displays wired to it and not the iGPU (more common). | |||
To enable sync mode, set the <code>hardware.nvidia.prime.reverseSync.enable</code> option to <code>true</code>: | |||
{{file|/etc/nixos/configuration.nix|nix|<nowiki> | {{file|/etc/nixos/configuration.nix|nix|<nowiki> | ||
Line 216: | Line 127: | ||
hardware.nvidia.prime = { | hardware.nvidia.prime = { | ||
reverseSync.enable = true; | reverseSync.enable = true; | ||
intelBusId = "PCI:0:2:0"; | intelBusId = "PCI:0:2:0"; | ||
nvidiaBusId = "PCI: | nvidiaBusId = "PCI:1:0:0"; | ||
# amdgpuBusId = "PCI:54:0:0"; | #amdgpuBusId = "PCI:54:0:0"; # If you have an AMD iGPU | ||
}; | }; | ||
} | } | ||
</nowiki>}} | </nowiki>}} | ||
== | == Tips and tricks == | ||
=== Check nixos-hardware === | === Check nixos-hardware === | ||
The [https://github.com/NixOS/nixos-hardware nixos-hardware] project attempts to provide configurations that address specific hardware quirks for different devices. It is possible that someone already wrote a hardware configuration for your device and that usually takes care of drivers. If so, follow the upstream documentation to enable the required modules. | |||
=== Multiple boot configurations === | === Multiple boot configurations === | ||
Line 241: | Line 149: | ||
{{file|/etc/nixos/configuration.nix|nix|<nowiki> | {{file|/etc/nixos/configuration.nix|nix|<nowiki> | ||
{ | { | ||
specialisation.on-the-go.configuration = { | |||
specialisation | |||
system.nixos.tags = [ "on-the-go" ]; | system.nixos.tags = [ "on-the-go" ]; | ||
hardware.nvidia = { | hardware.nvidia.prime = { | ||
offload = { | |||
enable = lib.mkForce true; | |||
enableOffloadCmd = lib.mkForce true; | |||
}; | |||
sync.enable = lib.mkForce false; | |||
}; | }; | ||
}; | }; | ||
} | } | ||
</nowiki>}} | </nowiki>}} | ||
(You can also add other settings here totally unrelated to | (You can also add other settings here totally unrelated to NVIDIA, such as power profiles, etc.) | ||
After rebuilding and rebooting, you'll see in your boot menu under each Generation an "on-the-go" option, which will let you boot into the on-to-go specialisation for that generation. | After rebuilding and rebooting, you'll see in your boot menu under each Generation an "on-the-go" option, which will let you boot into the on-to-go specialisation for that generation. | ||
Line 263: | Line 169: | ||
If you're using Nix-packaged software on a non-NixOS system, you'll need a workaround to get everything up-and-running. The [https://github.com/guibou/nixGL nixGL project] provides wrapper to use GL drivers on non-NixOS systems. You need to have GPU drivers installed on your distro (for kernel modules). With nixGL installed, you'll run <code>nixGL foobar</code> instead of <code>foobar</code>. | If you're using Nix-packaged software on a non-NixOS system, you'll need a workaround to get everything up-and-running. The [https://github.com/guibou/nixGL nixGL project] provides wrapper to use GL drivers on non-NixOS systems. You need to have GPU drivers installed on your distro (for kernel modules). With nixGL installed, you'll run <code>nixGL foobar</code> instead of <code>foobar</code>. | ||
Note that nixGL is not specific to | Note that nixGL is not specific to NVIDIA GPUs, and should work with just about any GPU. | ||
=== CUDA and using your GPU for compute === | === CUDA and using your GPU for compute === | ||
See the [[CUDA]] wiki page. | See the [[CUDA]] wiki page. | ||
=== | === Running Specific NVIDIA Driver Versions === | ||
To run a specific version of the NVIDIA driver in NixOS, you can customize your configuration by specifying the desired version along with the corresponding SHA256 hashes. Below is an example configuration for using NVIDIA driver version <code>555.58.02</code>: | |||
{{file|/etc/nixos/nvidia.nix|nix|<nowiki> | {{file|/etc/nixos/nvidia.nix|nix|<nowiki> | ||
{ | { config, ... }: | ||
{ | { | ||
hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.mkDriver { | |||
version = "555.58.02"; | |||
sha256_64bit = "sha256-xctt4TPRlOJ6r5S54h5W6PT6/3Zy2R4ASNFPu8TSHKM="; | |||
sha256_aarch64 = "sha256-xctt4TPRlOJ6r5S54h5W6PT6/3Zy2R4ASNFPu8TSHKM="; | |||
openSha256 = "sha256-ZpuVZybW6CFN/gz9rx+UJvQ715FZnAOYfHn5jt5Z2C8="; | |||
settingsSha256 = "sha256-ZpuVZybW6CFN/gz9rx+UJvQ715FZnAOYfHn5jt5Z2C8="; | |||
persistencedSha256 = lib.fakeSha256; | |||
}; | |||
}; | |||
</nowiki>}} | |||
In this configuration: | |||
* Replace <code>version</code> with the desired driver version. | |||
* Update the SHA256 hashes to match the new version you want to use. | |||
* After updating the configuration, run <code>sudo nixos-rebuild switch</code> to apply the changes and load the specified NVIDIA driver version. | |||
This allows you to pin the specific driver version being used in your NixOS installation. | |||
== Troubleshooting == | == Troubleshooting == | ||
=== Booting to text mode === | === Booting to text mode === | ||
If you encounter the problem of booting to text mode you might try adding the | If you encounter the problem of booting to text mode you might try adding the NVIDIA kernel module manually with: | ||
<syntaxHighlight lang="nix"> | <syntaxHighlight lang="nix"> | ||
Line 373: | Line 230: | ||
<code>powerManagement.enable = true</code> can sometimes fix this, but is itself unstable and is known to cause suspend issues. | <code>powerManagement.enable = true</code> can sometimes fix this, but is itself unstable and is known to cause suspend issues. | ||
If you have a modern | If you have a modern NVIDIA GPU (Turing [https://en.wikipedia.org/wiki/Turing_(microarchitecture)#Products_using_Turing] or later), you may also want to investigate the <code>hardware.nvidia.powerManagement.finegrained</code> option: [https://download.nvidia.com/XFree86/Linux-x86_64/460.73.01/README/dynamicpowermanagement.html] | ||
=== Black screen or 'nothing works' on laptops === | === Black screen or 'nothing works' on laptops === | ||
The kernel module<code>i915</code>for Intel or<code>amdgpu</code>for AMD may interfere with the | The kernel module<code>i915</code>for Intel or<code>amdgpu</code>for AMD may interfere with the NVIDIA driver. This may result in a black screen when switching to the virtual terminal, or when exiting the X session. A possible workaround is to disable the integrated GPU by blacklisting the module, using the following configuration option (see also [https://discourse.nixos.org/t/nvidia-gpu-and-i915-kernel-module/21307/3]): | ||
<syntaxHighlight lang="nix"> | <syntaxHighlight lang="nix"> | ||
Line 385: | Line 242: | ||
</syntaxHighlight> | </syntaxHighlight> | ||
= | == Disabling == | ||
=== Kernel modules from NVIDIA === | |||
Normally, NVIDIA's kernel modules should be completely disabled by removing <code>"nvidia"</code> from <code>services.xserver.videoDrivers</code>. If that fails to work, you can also manually blacklist the corresponding kernel modules:<syntaxhighlight lang="nix"> | |||
{ | |||
boot.blacklistedKernelModules = [ | |||
"nvidia" | |||
"nvidiafb" | |||
"nvidia-drm" | |||
"nvidia-uvm" | |||
"nvidia-modeset" | |||
]; | |||
} | |||
</syntaxhighlight> | |||
=== Nouveau === | |||
Nouveau can be disabled by blacklisting the <code>nouveau</code> kernel module:<syntaxhighlight lang="nix"> | |||
{ | |||
boot.blacklistedKernelModules = [ "nouveau" ]; | |||
} | |||
</syntaxhighlight>Note that disabling both NVIDIA kernel modules and Nouveau effectively disables the GPU entirely. | |||
boot.blacklistedKernelModules = [ "nouveau | |||
</ | |||
== Footnotes == | |||
[[Category:Video]] | [[Category:Video]] |
Latest revision as of 16:12, 26 October 2024
This page attempts to cover everything related to the use of NVIDIA GPUs on NixOS.
Enabling
Kernel modules from NVIDIA
Kernel modules from NVIDIA offer better performance than other alternatives, but make the system unfree by requiring proprietary userspace libraries that can interface with the kernel modules. Users that want to have a fully free and open-source system should use Nouveau instead.
To enable them, add "nvidia"
to the list of enabled video drivers defined by the services.xserver.videoDrivers
option.
configuration.nix
{
hardware.graphics.enable = true;
services.xserver.videoDrivers = [ "nvidia" ];
hardware.nvidia.open = true; # Set to false for proprietary drivers
}
Legacy branches
GPUs of the Kepler architecture or older (most GeForce 600/700/800M cards and older) are no longer supported by latest proprietary modules. Instead, users of these GPUs must use legacy branches that may still receive updates, as long as the GPUs themselves remain supported by NVIDIA. You can find which legacy branch you need to use by searching for your GPU model on NVIDIA's official legacy driver support list.
To use legacy branches, you need to set the hardware.nvidia.package
option to a package set named config.boot.kernelPackages.nvidiaPackages.legacy_<branch>
.
configuration.nix
{ config, ... }: # ← Required to get the packages used by the currently configured kernel, including drivers
{
# Last version that supports Kepler GPUs
hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.legacy_470;
}
Nixpkgs does not endeavor to support all legacy branches since older, unmaintained legacy branches can become incompatible with newer kernel and X server versions, and at some point it becomes infeasible to patch them to cooperate with modern software. You can find the list of supported legacy branches under in the Nixpkgs repository.
Beta/production branches
By default, modules from the stable branch are used, which come from latest release available for the current architecture — while x86-64 and aarch64 systems follow the "New Feature Branch" releases as they remain actively developed, 32-bit x86 and ARM systems remain on the 390.xx branch as that is the last branch with 32-bit support.
Instead of the stable branch, users can also switch to the beta branch, which has more new features and experimental changes at the risk of containing more bugs, or the production branch, a more conservative, well-tested stable version that is suitable for production use with minimum breakage, at the cost of being behind in terms of new features.
Using the beta and production branches are similar to how one would use legacy branches:
configuration.nix
{ config, ... }:
{
#hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.stable; # Default
hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.beta;
hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.production;
}
Nouveau
Nouveau is a set of free and open-source drivers for NVIDIA GPUs that provide 2D/3D acceleration for all NVIDIA GPUs. Its use is in general not recommended due to its considerably worse performance compared to NVIDIA's kernel modules, as it does not support reclocking (changing the GPU clock frequency on-demand) for many NVIDIA GPUs[2]. Nevertheless it remains a viable option for users who want a fully free and open-source operating system as it does not contain any proprietary components, unlike NVIDIA's kernel modules and userspace libraries.
Nouveau is enabled by default whenever graphics are enabled, and does not need any extra configuration.
configuration.nix
{
hardware.graphics.enable = true;
}
Configuring
Power management
Hybrid graphics with PRIME
Laptops often feature both an integrated GPU (iGPU) and a dedicated GPU (dGPU) in order to strive a balance between performance and power consumption — while the dGPU is used for performance-intensive tasks such as gaming, video editing, 3D rendering, compute jobs, etc., the iGPU can be used to render common 2D elements like application windows and the desktop environment.
PRIME, therefore, is a technology developed to facilitate the cooperation between the two GPUs and is critical for the laptop's graphical performance. Depending on your needs, you can configure PRIME in one of three modes, which have different tradeoffs in terms of performance and battery life.
Common setup
All PRIME configurations require setting the PCI bus IDs of the two GPUs. One easy way to do find their IDs is by running lspci
from the pciutils
package, and then finding devices that are classified as VGA controllers. After double checking that the listed devices are indeed your integrated and dedicated GPUs, you can then find the PCI IDs at the beginning of each line. Exact results may vary, but an example output might look like:
$ nix shell nixpkgs#pciutils -c "lspci" | grep "VGA"
0000:00:02.0 VGA compatible controller: Intel Corporation TigerLake-H GT1 [UHD Graphics] (rev 01)
0000:01:00.0 VGA compatible controller: NVIDIA Corporation GA106M [GeForce RTX 3060 Mobile / Max-Q] (rev a1)
Before putting them into your configuration, however, they must first be reformatted — take the last three numbers, convert them from hexadecimal to decimal, remove the leading zeroes, concatenate them with colons, and then add a PCI:
prefix. Then, they can be set under intelBusId
, nvidiaBusId
, or amdgpuBusId
in hardware.nvidia.prime
, depending on the manufacturer of the GPU:
configuration.nix
{
hardware.nvidia.prime = {
intelBusId = "PCI:0:2:0";
nvidiaBusId = "PCI:1:0:0";
#amdgpuBusId = "PCI:54:0:0"; # If you have an AMD iGPU
};
}
Offload mode
Offload mode puts your dGPU to sleep and lets the iGPU handle all tasks, except if you call the dGPU specifically by "offloading" an application to it. For example, you can run your laptop normally and it will use the energy-efficient iGPU all day, and then you can offload a game from Steam onto the dGPU to make the dGPU run that game only. For many, this is the most desirable option.
To enable offload mode, set the hardware.nvidia.prime.offload.enable
option to true
:
configuration.nix
{
hardware.nvidia.prime = {
offload.enable = true;
intelBusId = "PCI:0:2:0";
nvidiaBusId = "PCI:1:0:0";
#amdgpuBusId = "PCI:54:0:0"; # If you have an AMD iGPU
};
}
When you want to run a program on the dGPU, you only need to set a few environment variables for the driver to recognize that offload mode should be used. If hardware.nvidia.prime.offload.enableOffloadCmd
is set to true, NixOS will generate a wrapper script named nvidia-offload
that sets the right variables for you:
nvidia-offload
export __NV_PRIME_RENDER_OFFLOAD=1
export __NV_PRIME_RENDER_OFFLOAD_PROVIDER=NVIDIA-G0
export __GLX_VENDOR_LIBRARY_NAME=nvidia
export __VK_LAYER_NV_optimus=NVIDIA_only
exec "$@"
If everything is configured correctly, then running a program like glxgears
should use the iGPU, while running nvidia-offload glxgears
should only use the dGPU.
Sync mode
In sync mode, rendering is completely delegated to the dGPU, while the iGPU only displays the rendered framebuffers copied from the dGPU. Sync mode offers better performance and greatly reduces screen tearing, at the expense of higher power consumption since the dGPU will not go to sleep when not needed, as is the case in offload mode. Sync mode may also solve some issues with connecting a display in clamshell mode directly to the GPU.
To enable sync mode, set the hardware.nvidia.prime.sync.enable
option to true
:
/etc/nixos/configuration.nix
{
hardware.nvidia.prime = {
sync.enable = true;
intelBusId = "PCI:0:2:0";
nvidiaBusId = "PCI:1:0:0";
#amdgpuBusId = "PCI:54:0:0"; # If you have an AMD iGPU
};
}
Reverse sync mode
The difference between regular sync mode and reverse sync mode is that the dGPU is configured as the primary output device, allowing displaying to external displays wired to it and not the iGPU (more common).
To enable sync mode, set the hardware.nvidia.prime.reverseSync.enable
option to true
:
/etc/nixos/configuration.nix
{
hardware.nvidia.prime = {
reverseSync.enable = true;
intelBusId = "PCI:0:2:0";
nvidiaBusId = "PCI:1:0:0";
#amdgpuBusId = "PCI:54:0:0"; # If you have an AMD iGPU
};
}
Tips and tricks
Check nixos-hardware
The nixos-hardware project attempts to provide configurations that address specific hardware quirks for different devices. It is possible that someone already wrote a hardware configuration for your device and that usually takes care of drivers. If so, follow the upstream documentation to enable the required modules.
Multiple boot configurations
Imagine you have a laptop that you mostly use in clamshell mode (docked, connected to an external display and plugged into a charger) but that you sometimes use on the go.
In clamshell mode, using PRIME Sync is likely to lead to better performance, external display support, etc., at the cost of potentially (but not always) lower battery life. However, when using the laptop on the go, you may prefer to use offload mode.
NixOS supports "specialisations", which allow you to automatically generate different boot profiles when rebuilding your system. We can, for example, enable PRIME sync by default, but also create a "on-the-go" specialization that disables PRIME sync and instead enables offload mode:
/etc/nixos/configuration.nix
{
specialisation.on-the-go.configuration = {
system.nixos.tags = [ "on-the-go" ];
hardware.nvidia.prime = {
offload = {
enable = lib.mkForce true;
enableOffloadCmd = lib.mkForce true;
};
sync.enable = lib.mkForce false;
};
};
}
(You can also add other settings here totally unrelated to NVIDIA, such as power profiles, etc.)
After rebuilding and rebooting, you'll see in your boot menu under each Generation an "on-the-go" option, which will let you boot into the on-to-go specialisation for that generation.
Using GPUs on non-NixOS
If you're using Nix-packaged software on a non-NixOS system, you'll need a workaround to get everything up-and-running. The nixGL project provides wrapper to use GL drivers on non-NixOS systems. You need to have GPU drivers installed on your distro (for kernel modules). With nixGL installed, you'll run nixGL foobar
instead of foobar
.
Note that nixGL is not specific to NVIDIA GPUs, and should work with just about any GPU.
CUDA and using your GPU for compute
See the CUDA wiki page.
Running Specific NVIDIA Driver Versions
To run a specific version of the NVIDIA driver in NixOS, you can customize your configuration by specifying the desired version along with the corresponding SHA256 hashes. Below is an example configuration for using NVIDIA driver version 555.58.02
:
/etc/nixos/nvidia.nix
{ config, ... }:
{
hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.mkDriver {
version = "555.58.02";
sha256_64bit = "sha256-xctt4TPRlOJ6r5S54h5W6PT6/3Zy2R4ASNFPu8TSHKM=";
sha256_aarch64 = "sha256-xctt4TPRlOJ6r5S54h5W6PT6/3Zy2R4ASNFPu8TSHKM=";
openSha256 = "sha256-ZpuVZybW6CFN/gz9rx+UJvQ715FZnAOYfHn5jt5Z2C8=";
settingsSha256 = "sha256-ZpuVZybW6CFN/gz9rx+UJvQ715FZnAOYfHn5jt5Z2C8=";
persistencedSha256 = lib.fakeSha256;
};
};
In this configuration:
- Replace
version
with the desired driver version. - Update the SHA256 hashes to match the new version you want to use.
- After updating the configuration, run
sudo nixos-rebuild switch
to apply the changes and load the specified NVIDIA driver version.
This allows you to pin the specific driver version being used in your NixOS installation.
Troubleshooting
Booting to text mode
If you encounter the problem of booting to text mode you might try adding the NVIDIA kernel module manually with:
boot.initrd.kernelModules = [ "nvidia" ];
boot.extraModulePackages = [ config.boot.kernelPackages.nvidia_x11 ];
Screen tearing issues
First, try to switch to PRIME sync mode, as described above. If that doesn't work, try forcing a composition pipeline.
/etc/nixos/configuration.nix
hardware.nvidia.forceFullCompositionPipeline = true;
Flickering with Picom
~/.config/picom/picom.conf
unredir-if-possible = false;
backend = "xrender"; # try "glx" if xrender doesn't help
vsync = true;
Graphical corruption and system crashes on suspend/resume
powerManagement.enable = true
can sometimes fix this, but is itself unstable and is known to cause suspend issues.
If you have a modern NVIDIA GPU (Turing [1] or later), you may also want to investigate the hardware.nvidia.powerManagement.finegrained
option: [2]
Black screen or 'nothing works' on laptops
The kernel modulei915
for Intel oramdgpu
for AMD may interfere with the NVIDIA driver. This may result in a black screen when switching to the virtual terminal, or when exiting the X session. A possible workaround is to disable the integrated GPU by blacklisting the module, using the following configuration option (see also [3]):
# intel
boot.kernelParams = [ "module_blacklist=i915" ];
# AMD
boot.kernelParams = [ "module_blacklist=amdgpu" ];
Disabling
Kernel modules from NVIDIA
Normally, NVIDIA's kernel modules should be completely disabled by removing "nvidia"
from services.xserver.videoDrivers
. If that fails to work, you can also manually blacklist the corresponding kernel modules:
{
boot.blacklistedKernelModules = [
"nvidia"
"nvidiafb"
"nvidia-drm"
"nvidia-uvm"
"nvidia-modeset"
];
}
Nouveau
Nouveau can be disabled by blacklisting the nouveau
kernel module:
{
boot.blacklistedKernelModules = [ "nouveau" ];
}
Note that disabling both NVIDIA kernel modules and Nouveau effectively disables the GPU entirely.
Footnotes
- ↑ https://developer.nvidia.com/blog/nvidia-transitions-fully-towards-open-source-gpu-kernel-modules/
- ↑ https://www.phoronix.com/forums/forum/linux-graphics-x-org-drivers/open-source-nvidia-linux-nouveau/998310-nouveau-persevered-in-2017-for-open-source-nvidia-but-2018-could-be-much-better#post998316
- ↑ https://forums.developer.nvidia.com/t/the-all-new-outputsink-feature-aka-reverse-prime/129828/67