10.2. Hardware Requirements
As of XFree86 Version 220.127.116.11, released in January 1999, the video chipsets listed in this section are supported. The documentation included with your video adaptor 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 make, model, and chipset of the video card is. 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.
The following accelerated and nonaccelerated SVGA chipsets are supported:
Video cards using these chipsets are normally supported on all bus types, including the PCI and AGP.
All of these chipsets are supported in 256-color mode, some are supported in mono- and 16-color modes, and some are supported on higher color depths.
The monochrome server also supports generic VGA cards, using 64k of video memory in a single bank, the Hercules monochrome card, the Hyundai HGC1280, the Sigma LaserView, the Visa, and the Apollo monochrome cards.
The VGA16 server supports memory banking with the ET4000, Trident, ATI, NCR, OAK and Cirrus 6420 chipsets, allowing virtual display sizes up to about 1600x1200 (with 1 MB of video memory). The maximum display size for other chipsets and X servers varies, but you can get 1024x768 with most modern chipsets, often more (this also depends on the amount of video memory available and the color mode that you choose).
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 in the 2.2 kernel series via the FBDev server; this kernel has unaccelerated support for several chipsets for which there is not yet a dedicated server; it also supports acceleration on some hardware. If your graphics board is supported by any of the "ordinary" servers, you should use one of those, not the framebuffer server.
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 16 MB of RAM and a video card with a chipset listed earlier. For optimal performance, we suggest using an accelerated card, such as an S3-chipset card. You should check the documentation for XFree86 and verify that your particular card is supported before taking the plunge and purchasing expensive hardware. Benchmark ratings 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) 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 frame buffers for graphics and provide accelerated graphics hardware only as a high-priced add-on).
Your machine will need at least 8 MB of physical RAM, and 16 MB of virtual RAM (for example, 8 MB physical and 8 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 8 MB of RAM or more is necessary to run XFree86 comfortably. A system with 8 MB of physical RAM could run much more slowly (up to 10 times more slowly) than one with 16 MB or more.
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