NVIDIA/nvidia-drivers

Many Gentoo users have an nVidia chipset on their system. nVidia provides specific Linux drivers to boost the performance of your card. This guide informs you how to install and configure these drivers.

Introduction
The nVidia drivers in the tree are released by nVidia and are built against the Linux kernel. They contain a binary blob that does the heavy lifting for talking to the card. The drivers consist of two parts, a kernel module, and an X11 driver. Both parts are included in a single package. Due to the way nVidia has been packaging their drivers, you will need to make some choices before you install the drivers.

The nvidia-drivers package contains the latest drivers from nVidia with support for all cards, with several versions available depending on how old your card is. It uses an eclass to detect what kind of card you're running so that it installs the proper version.

Which version?
The nvidia-drivers package supports the full range of available nVidia cards. Multiple versions are available for installation, depending on the card(s) you have.

Newer cards such as the GeForce 400, 300, 200, 100, 9, 8, 7, and 6 series should use the latest drivers.

Older cards such as the GeForce FX 5 series should use the 173.x drivers, such as nvidia-drivers-173.14.15. For these cards, you should mask >=x11-drivers/nvidia-drivers-174.00 in your file. This will prevent newer versions of the driver which are incompatible with your card from being installed.

Old cards such as the GeForce 3 or GeForce 4 series require the 96.x drivers. For these cards, you should mask >=x11-drivers/nvidia-drivers-97.00 in your file.

The oldest NV2x-based cards (such as TNT, TNT2, GeForce, and GeForce 2) are no longer supported by nvidia-drivers. Instead, use an open-source driver: nouveau (recommended) or xf86-video-nv (old, deprecated).

You can check for driver compatibility for your card at to determine which driver supports it by viewing the README at its appropriate x86 or x86-64 release page.

Kernel Configuration
As mentioned above, the nVidia kernel driver installs and runs against your current kernel. It builds as a module, so it makes sense that your kernel must support the loading of kernel modules. If you used genkernel all to configure the kernel for you, then you're all set. If not, double check your kernel configuration so that this support is enabled:

You also need to enable Memory Type Range Register in your kernel:

Also, if you have an AGP graphics card, you can optionally enable agpgart support to your kernel, either compiled in or as a module. If you do not use the in-kernel agpgart, then the drivers will use their own agpgart implementation, called NvAGP. On certain systems, this performs better than the in-kernel agpgart, and on others, it performs worse. You will need to evaluate this on your own system to get the best performance. If you are unsure what to do, use the in-kernel agpgart:

Arch-specific notes
A framebuffer alternative is uvesafb, which can be installed parallel to nvidia-drivers.

Continuing with Kernel Configuration
The nvidia-drivers ebuild automatically discovers your kernel version based on the symlink. Please ensure that you have this symlink pointing to the correct sources and that your kernel is correctly configured. Please refer to the "Configuring the Kernel" section of the Gentoo Handbook for details on configuring your kernel.

First, you'll need to choose the right kernel source using eselect. If you are using gentoo-sources-2.6.34-r1, your kernel listing might look something like this:

In the above output, you'll notice that the linux-2.6.34-gentoo-r1 kernel is marked with an asterisk (*) to show that it is the symlinked kernel.

If the symlink is not pointing to the correct sources, you must update the link by selecting the number of your desired kernel sources, as in the example above.

Installing the Appropriate Drivers
Now it's time to install the drivers. You can do this by first following the X Server Configuration HOWTO and setting VIDEO_CARDS="nvidia" in. When you install the X server, it will then install the right version of nvidia-drivers for you.

Once the installation has finished, run modprobe nvidia to load the kernel module into memory. If this is an upgrade, you should remove the previous module first.

To prevent you having to manually load the module on every bootup, you probably want to have this done automatically each time you boot your system, so edit and add nvidia to it.

Configuring the X Server
Once the appropriate drivers are installed you need to configure your X Server to use the nvidia driver instead of the default nv driver.

Open with your favorite editor (such as nano or vim) and go to the Device section. In that section, change the Driver line:

Then go to the Module section and make sure the glx module gets loaded while the dri module doesn't:

Next, in section Screen, make sure that either the DefaultDepth directive is set to 16 or 24, or that you only have Display subsections with Depth settings of 16 or 24. Without it, the nVidia GLX extensions will not start.

Run eselect so that the X Server uses the nVidia GLX libraries:

Adding your Users to the video Group
You have to add your user to the video group so he has access to the nVidia device files:

This might not be totally necessary if you aren't using udev but it doesn't hurt either and makes your system future-proof.

Testing your Card
To test your nVidia card, fire up X and run glxinfo, which is part of the mesa-progs package. It should say that direct rendering is activated:

To monitor your FPS, run glxgears.

Enabling nvidia Support
Some tools, such as mplayer and xine-lib, use a local USE flag called xvmc which enables XvMCNVIDIA support, useful when watching high resolution movies. Add in xvmc in your USE variable in or add it as USE flag to media-video/mplayer and/or media-libs/xine-lib in.

There are also some applications that use the nvidia USE flag, so you may want to add it to.

Then, run emerge -uD --newuse world to rebuild the applications that benefit from the USE flag change.

Using NVidia Settings Tool
nVidia also provides you with a settings tool. This tool allows you to monitor and change graphical settings without restarting the X server and is available through Portage as media-video/nvidia-settings. As mentioned earlier, it will be pulled in automatically if you install the drivers with the gtk USE flag set in or in.

Getting 2D to work on machines with 4Gb or more memory
If you are having troubles with the nVidia 2D acceleration it is likely that you are unable to set up a write-combining range with MTRR. To verify, check the contents of :

Every line should contain "write-back" or "write-combining". If you see a line with "uncachable" in it you will need to change a BIOS setting to fix this.

Reboot and enter the BIOS, then find the MTRR settings (probably under "CPU Settings"). Change the setting from "continuous" to "discrete" and boot back into Linux. You will now find out that there is no "uncachable" entry anymore and 2D acceleration now works without any glitches.

When I attempt to load the kernel module I receive a "no such device"
This usually occurs when you don't have a matching video card. Make sure that you have an nVidia-powered graphical card (you can double-check this using lspci).

If you are confident that you have an nVidia card, check your BIOS and see if the directive Assign IRQ to VGA is set.

Documentation
The nVidia driver package also comes with comprehensive documentation. This is installed into /usr/share/doc and can be viewed with the following command:

Kernel module parameters
The nvidia kernel module accepts a number of parameters (options) which you can use to tweak the behaviour of the driver. Most of these are mentioned in the documentation. To add or change the values of these parameters, edit the file /etc/modprobe.d/nvidia.conf. Remember to run update-modules after modifying this file, and bear in mind that you will need to reload the nvidia module before the new settings take effect.

Edit /etc/modprobe.d/nvidia.conf in your favourite editor:

Update module information:

Unload the nvidia module...

...and load it once again:

Advanced X configuration
The GLX layer also has a plethora of options which can be configured. These control the configuration of TV out, dual displays, monitor frequency detection, etc. Again, all of the available options are detailed in the documentation.

If you wish to use any of these options, you need to list them in the relevant Device section of your X config file (usually /etc/X11/xorg.conf). For example, suppose I wanted to disable the splash logo:

Acknowledgements
We would like to thank the following authors and editors for their contributions to this guide: Sven Vermeulen, Joshua Saddler, M Curtis Napier and Chris Gianelloni.