As of XFree86 Version 4.2.0, released in January 2002, the video chipsets listed in this section are supported. The documentation included with your video adapter should specify the chipset used. If you are in the market for a new video card, or are buying a new machine that comes with a video card, have the vendor find out exactly what the video card's make, model, and chipset are. This may require the vendor to call technical support on your behalf; vendors usually will be happy to do this. Many PC hardware vendors will state that the video card is a "standard SVGA card" that "should work" on your system. Explain that your software (mention Linux and XFree86!) does not support all video chipsets and that you must have detailed information.
A good source for finding out whether your graphics board is supported and which X server it needs is http://www.xfree86.org/cardlist.html.
You can also determine your video card chipset by running the SuperProbe program included with the XFree86 distribution. This is covered in more detail later.
The following accelerated and nonaccelerated SVGA chipsets are supported (sorted by manufacturer):
It should be noted that the XFree86 project recently switched to an entirely new driver architecture, which is much more flexible than the old one and will enable more timely support of new graphics hardware. However, this also means that not all the drivers that existed in previous versions have been ported to the new architecture yet. Thus, a fair number of (mostly older) graphics chips are supported by the previous version (3.3.6), but are not supported by the current version. If this is the case with your graphics hardware (the driver list at http://xfree86.org will tell you), you might want to consider installing the old version.
Video cards using these chipsets are normally supported on all bus types, including the PCI and AGP.
All these chipsets are supported in 256-color mode, some are supported in mono- and 16-color modes, and some are supported in higher color depths.
This list will undoubtedly expand as time passes. The release notes for the current version of XFree86 should contain the complete list of supported video chipsets. Please also always see the README file for your particular chipset.
Besides those chipsets, there is also support for the framebuffer device starting with the 2.2 kernel series via the fbdev driver. If your chipset is supported by the normal X server drivers, you should use those for better performance, but if it is not, you may still be able to run X by using the framebuffer. On some hardware, even the framebuffer device provides accelerated graphics.
One problem faced by the XFree86 developers is that some video card manufacturers use nonstandard mechanisms for determining clock frequencies used to drive the card. Some of these manufacturers either don't release specifications describing how to program the card, or require developers to sign a nondisclosure statement to obtain the information. This would obviously restrict the free distribution of the XFree86 software, something that the XFree86 development team is not willing to do.
The suggested minimum setup for XFree86 under Linux is a `486 machine with at least 32 MB of RAM and a video card with a chipset listed earlier. You should check the documentation for XFree86 and verify that your particular card is supported before taking the plunge and purchasing expensive hardware. Benchmark rating comparisons for various video cards under XFree86 are posted to the Usenet newsgroups comp.windows.x.i386unix and comp.os.linux.misc regularly.
As a side note, one author's (Kalle's) secondary personal Linux system is an AMD K6-2 with 128 MB of RAM and is equipped with a PCI Permedia II chipset card with 8 MB of DRAM. This setup is already a lot faster with respect to display speed than many workstations. XFree86 on a Linux system with an accelerated SVGA card will give you much greater performance than that found on commercial Unix workstations (which often employ simple framebuffers for graphics and provide accelerated graphics hardware only as a high-priced add-on).
Your machine will need at least 16 MB of physical RAM and 32 MB of virtual RAM (for example, 16 MB physical and 16 MB swap). Remember that the more physical RAM you have, the less the system will swap to and from disk when memory is low. Because swapping is inherently slow (disks are very slow compared to memory), having 16 MB or more of RAM is necessary to run XFree86 comfortably. A system with 16 MB of physical RAM could run much more slowly (up to 10 times more slowly) than one with 32 MB or more.
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