Nouveau

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This article covers the open-source Nouveau driver for NVIDIA graphics cards. For information about the proprietary driver, see NVIDIA.

Find your card's code name (a more detailed list is available on Wikipedia), and compare it with the feature matrix for supported features.

Installation

Install the mesa package, which provides the DRI driver for 3D acceleration.

Also see Hardware video acceleration.

Loading

The Nouveau kernel module should load automatically on system boot. If it does not happen, then:

  • Make sure you do not have nomodeset or vga= as a kernel parameter, since Nouveau requires kernel mode-setting.
  • Also, check that you do not have Nouveau disabled using any modprobe blacklisting technique within /etc/modprobe.d/ or /usr/lib/modprobe.d/.
  • If all above still fails to load nouveau check dmesg for an opcode error. Add nouveau.config=NvBios=PRAMIN to your Kernel parameters to prevent module unloading.[1]
  • Check if /etc/X11/xorg.conf exists and is referencing nvidia driver. It is probably a good idea to rename the file.

Enable early KMS

Tip: If you have problems with the resolution, check Kernel mode setting#Forcing modes and EDID.

Kernel mode setting (KMS) is required by the Nouveau driver. By default, the KMS is done after the other kernel modules are loaded. You will see the text "Loading modules" and the size of the text may change, possibly with an undesirable flicker. See the Nouveau KernelModeSetting page for more details.

It is also possible to start the KMS as early as possible in the boot process, when the initramfs is loaded.

To do this, add nouveau to the MODULES array in /etc/mkinitcpio.conf (module names are separated by spaces): 

MODULES=(... nouveau ...)

If you are using a custom EDID file, you should embed it into initramfs as well: 

/etc/mkinitcpio.conf
FILES="/lib/firmware/edid/your_edid.bin"

To finish, regenerate the initramfs.

Tips and tricks

Keep NVIDIA driver installed

If you want to keep the proprietary NVIDIA driver installed (and are not using OpenGL), but want to use the Nouveau driver, comment out nouveau blacklisting in /etc/modprobe.d/nouveau_blacklist.conf, /usr/lib/modprobe.d/nvidia.conf, or /usr/lib/modprobe.d/nvidia-dkms.conf modifying it as follows: 

#blacklist nouveau

And tell Xorg to load nouveau instead of nvidia by creating the file /etc/X11/xorg.conf.d/20-nouveau.conf with the following content: 

Section "Device"
    Identifier "Nvidia card"
    Driver "nouveau"
EndSection

If you already used the NVIDIA driver, and want to test Nouveau without reboot, make sure the 'nvidia' module is no longer loaded: 

# rmmod nvidia

Then load the 'nouveau' module: 

# modprobe nouveau

And check that it loaded fine by looking at kernel messages: 

# dmesg

Installing the latest development packages

To get the latest Nouveau improvements

Dual head

See Multihead#RandR how to setup multiple monitors by using RandR.

Setting console resolution

You can pass the resolution to nouveau with the video= kernel line option (see KMS).

Power management

The lack of proper power management in the nouveau driver is one of the most important causes of performance issues, since most cards will remain in their lower power state with lower clocks during their use. Experimental support for GPU reclocking is available for some cards (see the Nouveau PowerManagement page) and since kernel 4.5 can be controlled through a debugfs interface located at /sys/kernel/debug/dri/*/pstate.

For example, to check the available power states and the current setting for the first card in your system, run: 

# cat /sys/kernel/debug/dri/0/pstate

It is also possible to manually set/force a certain power state by writing to said interface: 

# echo pstate > /sys/kernel/debug/dri/0/pstate
Warning: The support for reclocking is highly experimental. Manually setting the power state may hang your system, cause corruption or overheat your card.

Fan control

If it is implemented for your card you can configure fan control via /sys. 

$ find /sys -name pwm1_enable
/sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/hwmon/hwmon1/pwm1_enable
$ readlink /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/driver
../../../../bus/pci/drivers/nouveau

pwm1_enable can be set to 0, 1 or 2 meaning NONE, MANUAL and AUTO fan control. If set to manual fan control, you can set pwm1 manually, for example to 40 for 40%.

Warning: Use at your own risk! Do not overheat your card!

You can also set it by udev rule: 

$ cat /etc/udev/rules.d/50-nouveau-hwmon.rules
ACTION=="add", SUBSYSTEM=="hwmon", DRIVERS=="nouveau", ATTR{pwm1_enable}="2"

Sources:

Optimus

You have two solutions to use Optimus on a laptop (aka hybrid graphics, when you have two GPUs on your laptop): bumblebee and PRIME

Vertical Sync

Xorg compositors are prone to show issues with Nouveau. Unlike most of them, Picom offers lots of options to tweak for a smoother and tearing free result. A configuration which is expected to deliver a good result would be the following: 

$ picom -b --unredir-if-possible --backend xr_glx_hybrid --vsync --use-damage --glx-no-stencil
Tip: Do not forget to turn off compositing of your DE's window manager like KWin when using a different compositor.

Troubleshooting

Add drm.debug=14 and log_buf_len=16M to your kernel parameters to turn on video debugging:

Create verbose Xorg log: 

$ startx -- -logverbose 9 -verbose 9

View loaded video module parameters and values: 

$ modinfo -p video

Disable MSI

If you are still having problems loading the module or starting X server append nouveau.config=NvMSI=0 to your Kernel parameters.

Source: https://bugs.freedesktop.org/show_bug.cgi?id=78441

Phantom output issue

It is possible for the nouveau driver to detect "phantom" outputs. For example, both VGA-1 and LVDS-1 are shown as connected but only LVDS-1 is present.

This causes display problems and/or prevent suspending on lid closure.

Kernel parameters

The problem can be overcome by disabling the phantom output (VGA-1 in the examples given) with Kernel parameters: 

video=VGA-1:d

Where d = disable.

The nouveau kernel module also has an option to disable TV-out detection [2]: 

 tv_disable=1

Xorg configuration

The phantom output can be disabled in Xorg by adding the following to /etc/X11/xorg.conf.d/20-nouveau.conf: 

Section "Monitor"
Identifier "VGA-1"
Option "Ignore" "1"
EndSection

Source: https://web.archive.org/web/20170118202740/http://gentoo-en.vfose.ru/wiki/Nouveau#Phantom_and_unpopulated_output_connector_issues

Xrandr

Xrandr can disable the output: 

 $ xrandr --output VGA-1 --off

This can be added to the xinit configuration.

Random lockups with kernel error messages

Specific Nvidia chips with Nouveau may give random system lockups and more commonly throw many kernel messages, seen with dmesg. Try adding the nouveau.noaccel=1 kernel parameter. See Fedora:Common kernel problems#Systems with nVidia adapters using the nouveau driver lock up randomly for more information.

As an alternative you can also use the QT_XCB_FORCE_SOFTWARE_OPENGL=1 environment variable to disable OpenGL acceleration in Qt applications.

Flat Panel Table Invalid

NVIDIA graphics cards with recent chipsets can cause startup issues - this includes X11 being unable to start and lspci freezing indefinitely[3][4][5][6][7].

This can break live distributions/installation media. This can be detected either by running lspci, or checking the systemd journal for the error: 

nouveau E[     DRM]Pointer to flat panel table invalid

The system may start if the Nouveau driver is disabled by passing the following kernel parameters: 

modprobe.blacklist=nouveau

The Nouveau driver can then be loaded using 

# modprobe nouveau

The system should then function correctly. If you have another Nvidia graphics card, or just want to be safe, you can disable the offending card using: 

$ echo 1 > /sys/bus/pci/devices/[card device id]/remove