GLIDE(4)                    Kernel Interfaces Manual                    GLIDE(4)

       glide - Glide video driver

       Section "Device"
         Identifier "devname"
         Driver "glide"

       glide is an Xorg driver for Glide capable video boards (such as 3Dfx
       Voodoo boards). This driver is mainly for Voodoo 1 and Voodoo 2 boards,
       later boards from 3Dfx have 2D built-in and you should preferably use a
       driver separate for those boards or the fbdev(4) driver.  This driver is
       a bit special because Voodoo 1 and 2 boards are very much NOT made for
       running 2D graphics. Therefore, this driver uses no hardware acceleration
       (since there is no acceleration for 2D, only 3D). Instead it is
       implemented with the help of a "shadow" framebuffer that resides entirely
       in RAM. Selected portions of this shadow framebuffer are then copied out
       to the Voodoo board at the right time. Because of this, the speed of the
       driver is very dependent on the CPU. But since the CPU is nowadays
       actually rather fast at moving data, we get very good speed anyway,
       especially since the whole shadow framebuffer is in cached RAM.

       This driver supports 16 and 24 bit color modes. The 24 bit color mode
       uses a 32 bit framebuffer (it has no support for 24 bit packed-pixel
       framebuffers). Notice that the Voodoo boards can only display 16 bit
       color, but the shadow framebuffer can be run in 24 bit color. The point
       of supporting 24 bit mode is that this enables you to run in a multihead
       configuration with Xinerama together with another board that runs in real
       24 bit color mode. (All boards must run the same color depth when you use

       Resolutions supported are: 640x480, 800x600, 960x720, 1024x768, 1280x1024
       and 1600x1200. Note that not all modes will work on all Voodoo boards. It
       seems that Voodoo 2 boards support no higher than 1024x768 and Voodoo 1
       boards can go to 800x600. If you see a message like this in the output
       from the server:

         (EE) GLIDE(0): grSstWinOpen returned ...

       Then you are probably trying to use a resolution that is supported by the
       driver but not supported by the hardware.

       Refresh rates supported are: 60Hz, 75Hz and 85Hz. The refresh rate used
       is derived from the normal mode line according to the following table:

       Mode-line refresh rate      Used refresh rate

          0-74 Hz
                                     60 Hz

         74-84 Hz
                                     75 Hz

         84-   Hz
                                     85 Hz

       Thus, if you use a modeline that for example has a 70Hz refresh rate you
       will only get a 60Hz refresh rate in actuality.

       Selecting which Voodoo board to use with the driver is done by using an
       option called "GlideDevice" in the "Device" section. (If you don't have
       this option present then the first board found will be selected for that
       Device section). For example: To use the first Voodoo board, use a
       "Device" section like this, for example:

       Section "Device"
          Identifier  "Voodoo"
          Driver      "glide"
          Option      "dpms" "on"
          Option      "GlideDevice" "0"

       And if you have more than one Voodoo board, add another "Device" section
       with a GlideDevice option with value 1, and so on. (You can use more than
       one Voodoo board, but SLI configured boards will be treated as a single

       Multihead and Xinerama configurations are supported.

       Limited support for DPMS screen saving is available. The "standby" and
       "suspend" modes are just painting the screen black. The "off" mode turns
       the Voodoo board off and thus works correctly.

       This driver does not support a virtual screen size different from the
       display size.

       The glide driver supports any board that can be used with Glide (such as
       3Dfx Voodoo boards)

       Please refer to xorg.conf(5) for general configuration details.  This
       section only covers configuration details specific to this driver.

       The following driver Options are supported:

       Option "OnAtExit" "boolean"
              If true, will leave the Voodoo board on when the server exits.
              Useful in a multihead setup when only the Voodoo board is
              connected to a second monitor and you don't want that monitor to
              lose signal when you quit the server. Put this option in the
              Device section.  Default: off.

       Option "GlideDevice" "integer"
              Selects which Voodoo board to use. (Or boards, in an SLI
              configuration).  The value should be 0 for the first board, 1 for
              the second and so on.  If it is not present, the first Voodoo
              board found will be selected.  Put this option in the Device

       Here is an example of a part of an xorg.conf file that uses a multihead
       configuration with two monitors. The first monitor is driven by the fbdev
       video driver and the second monitor is driven by the glide driver.

       Section "Monitor"
          Identifier      "Monitor 1"
          VendorName      "Unknown"
          ModelName       "Unknown"
          HorizSync       30-70
          VertRefresh     50-80

          # 1024x768 @ 76 Hz, 62.5 kHz hsync
          Modeline "1024x768" 85 1024 1032 1152 1360 768 784 787 823

       Section "Monitor"
          Identifier      "Monitor 2"
          VendorName      "Unknown"
          ModelName       "Unknown"
          HorizSync       30-70
          VertRefresh     50-80

          # 1024x768 @ 76 Hz, 62.5 kHz hsync
          Modeline "1024x768" 85 1024 1032 1152 1360 768 784 787 823

       Section "Device"
          Identifier  "fb"
          Driver      "fbdev"
          Option      "shadowfb"
          Option      "dpms" "on"
          # My video card is on the AGP bus which is usually
          # located as PCI bus 1, device 0, function 0.
          BusID       "PCI:1:0:0"

       Section "Device"
          # I have a Voodoo 2 board
          Identifier  "Voodoo"
          Driver      "glide"
          Option      "dpms" "on"
          # The next line says I want to use the first board.
          Option      "GlideDevice" "0"

       Section "Screen"
         Identifier   "Screen 1"
         Device  "fb"
         Monitor "Monitor 1"
         DefaultDepth 16
         Subsection "Display"
           Depth 16
           Modes "1024x768"

       Section "Screen"
         Identifier   "Screen 2"
         Device  "Voodoo"
         Monitor "Monitor 2"
         DefaultDepth 16
         Subsection "Display"
           Depth 16
           Modes "1024x768"

       Section "ServerLayout"
         Identifier   "Main Layout"
         # Screen 1 is to the right and screen 2 is to the left
         Screen  "Screen 2"
         Screen  "Screen 1" "" "" "Screen 2" ""

       If you use this configuration file and start the server with the
       +xinerama command line option, the two monitors will be showing a single
       large area where windows can be moved between monitors and overlap from
       one monitor to the other. Starting the X server with the Xinerama
       extension can be done for example like this:

       $ xinit -- +xinerama


       Xorg(1), xorg.conf(5), Xserver(1), X(7)

       Author: Henrik Harmsen.

X Version 11                 xf86-video-glide 1.2.2                     GLIDE(4)