This can be caused by a variety of problems, such as PCI IRQ routing errors, I/O APIC problems or conflicts with other devices sharing the IRQ (or their drivers).

If possible, configure your system such that your graphics card does not share its IRQ with other devices (try moving the graphics card to another slot if applicable, unload/disable the driver(s) for the device(s) sharing the card's IRQ, or remove/disable the device(s)).

If X starts but you have trouble with OpenGL, you most likely have a problem with other libraries in the way, or there are stale symlinks. See Appendix C, Installed Components for details.

You should also check that the correct extensions are present;

    % xdpyinfo

should show the “GLX” and “NV-GLX” extensions present. If these two extensions are not present, then there is most likely a problem loading the glx module, or it is unable to implicitly load GLcore. Check your X config file and make sure that you are loading glx (see Chapter 3, Configuring X for the NVIDIA Driver). If your X config file is correct, then check the X log file for warnings/errors pertaining to GLX. Also check that all of the necessary symlinks are in place (refer to Appendix C, Installed Components).

This problem occurs with DDC and "blue line" stereo glasses, that get the stereo signal from one video port of the graphics card. When a X screen does not display any stereo drawable the stereo signal is disabled on the associated video port.

Forcing stereo flipping allows the stereo glasses to shutter continuously. This can be done by enabling the OpenGL control "Force Stereo Flipping" in nvidia-settings, or by setting the X configuration option "ForceStereoFlipping" to "1".

There are two cases where this may occur. If the displays are attached to the same GPU, and one of them is out of sync with the stereo glasses, you will need to reconfigure your monitors to drive identical mode timings; please see Appendix L, Programming Modes for details.

If the displays are attached to different GPUs, the only way to synchronize stereo across the displays is with specialized frame lock hardware, which is only supported on certain Quadro cards. Please see Appendix W, Frame Lock and Genlock for details. This applies to seperate GPUs on seperate cards as well as seperate GPUs on the same card, such as Quadro FX 4500 X2. Note that the Quadro FX 4500 X2 only provides a single DIN connector for stereo, tied to the bottommost GPU. In order to synchronize onboard stereo on the other GPU you must use frame lock hardware.

The system bios has not properly setup your graphics card; FreeBSD can't currently setup PCI devices that the BIOS leaves unconfigured. Please uncheck "PNP-OS" in your system bios.

On certain FreeBSD kernels, it may be necessary to add the following line to /boot/loader.conf:

hw.pci.allow_unsupported_io_range="1"

This should allow the NVIDIA kernel module to attach.

Nothing will work if the NVIDIA kernel module does not function properly. If you see anything in the X log file like

(EE) NVIDIA(0): Failed to initialize the NVIDIA kernel module!

then there is most likely a problem with the NVIDIA kernel module.

The NVIDIA kernel module may print error messages indicating a problem -- to view these messages please check the output of dmesg, /var/log/messages, or wherever syslog is directed to place kernel messages. These messages are prepended with "NVRM".

Due to differences between the gtk+-2.x ports packages included with different FreeBSD 5.x releases, the prebuilt nvidia-settings binary shipped with the NVIDIA driver may not work with FreeBSD releases more recent than FreeBSD 5.3.

If you have a recent ports package of gtk+-2.x and gmake installed on your system, you can build the nvidia-installer utility from source to solve this problem.

Download nvidia-settings-1.0.tar.gz (or the latest version) from ftp://download.nvidia.com/XFree86/nvidia-settings You can then extract, build and install it (to /usr/local/bin) with:

    % gmake install

Depending on the shell you are using, you may need to force it to recompute its internal table of executable files present in the directories listed in the $PATH variable. Assuming you are using the FreeBSD default shell you can do so by issuing the command:

    % rehash

When initialized by an application executed with 'root' privileges, the NVIDIA Linux OpenGL library, shipped with the NVIDIA FreeBSD graphics driver for Linux ABI compatibility, will attempt to load the NVIDIA Linux kernel module and fail because /sbin/modprobe is absent. You can work around this problem by creating a symbolic link from /usr/bin/true to /compat/linux/sbin/modprobe:

    % ln -s /usr/bin/true /compat/linux/sbin/modprobe

Your stability problems may be AGP-related. See Appendix H, Configuring AGP for details.

The application is probably using a different library still on your system, rather than the NVIDIA supplied OpenGL library. Please see Appendix C, Installed Components for details.

Quake2 requires some minor setup to get it going. First, in the Quake2 directory, the install creates a symlink called libGL.so that points at libMesaGL.so. This symlink should be removed or renamed. Second, in order to run Quake2 in OpenGL mode, you must type

    % quake2 +set vid_ref glx +set gl_driver libGL.so

Quake2 does not seem to support any kind of full-screen mode, but you can run your X server at the same resolution as Quake2 to emulate full-screen mode.

Integrated graphics have more strict memory bandwidth limitations that limit the resolution and refresh rate of the modes you request. To work around this, you can reduce the maximum refresh rate by lowering the upper value of the VertRefresh range in the Monitor section of your X config file. Though not recommended, you can disable the memory bandwidth test with the NoBandWidthTest X config file option.

Most of the startx delay problems we have found are caused by incorrect data in video BIOSes about what display devices are possibly connected or what i2c port should be used for detection. You can work around these problems with the X config option IgnoreDisplayDevices (please see the description in Appendix D, X Config Options).

Incorrectly sized fonts are generally caused by incorrect DPI (Dots Per Inch) information. You can check what X thinks the physical size of your monitor is, by running:

 % xdpyinfo | grep dimensions

This will report the size in pixels, and in millimeters.

If these numbers are wrong, you can correct them by modifying the X server's DPI setting. See Appendix X, Dots Per Inch for details.

There are some known timing and signal integrity issues on ALi chipsets. The following tips may help stabilize problematic ALI systems: