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xorg.conf(5)                  File Formats Manual                 xorg.conf(5)



NAME
       xorg.conf - configuration File for Xorg X server

INTRODUCTION
       Xorg  supports several mechanisms for supplying/obtaining configuration
       and run-time parameters: command line options,  environment  variables,
       the   xorg.conf   configuration   file,  auto-detection,  and  fallback
       defaults.  When the same information is supplied in more than one  way,
       the  highest  precedence  mechanism is used.  The list of mechanisms is
       ordered from highest precedence to lowest.  Note that not  all  parame-
       ters  can  be  supplied  via  all  methods.  The available command line
       options and environment variables (and some defaults) are described  in
       the  Xserver(1)  and  Xorg(1)  manual  pages.   Most configuration file
       parameters, with their defaults, are described below.  Driver and  mod-
       ule  specific  configuration  parameters  are described in the relevant
       driver or module manual page.

DESCRIPTION
       Xorg uses a configuration file called xorg.conf for its initial  setup.
       This  configuration  file  is searched for in the following places when
       the server is started as a normal user:

           /etc/X11/<cmdline>
           /usr/etc/X11/<cmdline>
           /etc/X11/$XORGCONFIG
           /usr/etc/X11/$XORGCONFIG
           /etc/X11/xorg.conf-4
           /etc/X11/xorg.conf
           /etc/xorg.conf
           /usr/etc/X11/xorg.conf.<hostname>
           /usr/etc/X11/xorg.conf-4
           /usr/etc/X11/xorg.conf
           /usr/lib/X11/xorg.conf.<hostname>
           /usr/lib/X11/xorg.conf-4
           /usr/lib/X11/xorg.conf

       where &lt;cmdline&gt; is a relative path (with no ".." components)  specified
       with  the -config command line option, $XORGCONFIG is the relative path
       (with no ".." components) specified by that environment  variable,  and
       &lt;hostname&gt;   is   the   machine's  hostname  as  reported  by  gethost-
       name(__oslibmansuffix__).

       When the Xorg server is started by the "root"  user,  the  config  file
       search locations are as follows:

           <cmdline>
           /etc/X11/<cmdline>
           /usr/etc/X11/<cmdline>
           $XORGCONFIG
           /etc/X11/$XORGCONFIG
           /usr/etc/X11/$XORGCONFIG
           $HOME/xorg.conf
           /etc/X11/xorg.conf-4
           /etc/X11/xorg.conf
           /etc/xorg.conf
           /usr/etc/X11/xorg.conf.<hostname>
           /usr/etc/X11/xorg.conf-4
           /usr/etc/X11/xorg.conf
           /usr/lib/X11/xorg.conf.<hostname>
           /usr/lib/X11/xorg.conf-4
           /usr/lib/X11/xorg.conf

       where  &lt;cmdline&gt;  is  the  path specified with the -config command line
       option (which may be absolute or relative),  $XORGCONFIG  is  the  path
       specified by that environment variable (absolute or relative), $HOME is
       the path specified by  that  environment  variable  (usually  the  home
       directory),  and  &lt;hostname&gt;  is  the machine's hostname as reported by
       gethostname(__oslibmansuffix__).

       The xorg.conf file is composed of a number of  sections  which  may  be
       present in any order.  Each section has the form:

           Section  "SectionName"
               SectionEntry
               ...
           EndSection

       The section names are:

           Files          File pathnames
           ServerFlags    Server flags
           Module         Dynamic module loading
           InputDevice    Input device description
           Device         Graphics device description
           VideoAdaptor   Xv video adaptor description
           Monitor        Monitor description
           Modes          Video modes descriptions
           Screen         Screen configuration
           ServerLayout   Overall layout
           DRI            DRI-specific configuration
           Vendor         Vendor-specific configuration

       The  following obsolete section names are still recognised for compati-
       bility purposes.  In new config files, the InputDevice  section  should
       be used instead.

           Keyboard       Keyboard configuration
           Pointer        Pointer/mouse configuration

       The old XInput section is no longer recognised.

       The ServerLayout sections are at the highest level.  They bind together
       the input and output devices that will be used in a session.  The input
       devices are described in the InputDevice sections.  Output devices usu-
       ally consist of multiple independent components (e.g., a graphics board
       and  a  monitor).   These multiple components are bound together in the
       Screen sections, and it is these that are referenced by the  ServerLay-
       out section.  Each Screen section binds together a graphics board and a
       monitor.  The graphics boards are described in the Device sections, and
       the monitors are described in the Monitor sections.

       Config  file  keywords  are  case-insensitive,  and  "_" characters are
       ignored.  Most strings (including Option names) are also  case-insensi-
       tive, and insensitive to white space and "_" characters.

       Each  config  file  entry  usually  takes up a single line in the file.
       They consist of a keyword, which is possibly followed by  one  or  more
       arguments,  with the number and types of the arguments depending on the
       keyword.  The argument types are:

           Integer     an integer number in decimal, hex or octal
           Real        a floating point number
           String      a string enclosed in double quote marks (")

       Note: hex integer values must be prefixed with "0x", and  octal  values
       with "0".

       A  special  keyword called Option may be used to provide free-form data
       to various components of the server.  The Option keyword  takes  either
       one  or  two  string  arguments.  The first is the option name, and the
       optional second argument is  the  option  value.   Some  commonly  used
       option value types include:

           Integer     an integer number in decimal, hex or octal
           Real        a floating point number
           String      a sequence of characters
           Boolean     a boolean value (see below)
           Frequency   a frequency value (see below)

       Note  that  all  Option  values,  not just strings, must be enclosed in
       quotes.

       Boolean options may optionally have a value specified.  When  no  value
       is specified, the option's value is TRUE.  The following boolean option
       values are recognised as TRUE:

           1, on, true, yes

       and the following boolean option values are recognised as FALSE:

           0, off, false, no

       If an option name is prefixed with  "No",  then  the  option  value  is
       negated.

       Example: the following option entries are equivalent:

           Option "Accel"   "Off"
           Option "NoAccel"
           Option "NoAccel" "On"
           Option "Accel"   "false"
           Option "Accel"   "no"

       Frequency  option  values  consist  of a real number that is optionally
       followed by one of the following frequency units:

           Hz, k, kHz, M, MHz

       When the unit name is omitted, the correct  units  will  be  determined
       from  the  value  and  the expectations of the appropriate range of the
       value.  It is recommended that the units always be specified when using
       frequency option values to avoid any errors in determining the value.

FILES SECTION
       The  Files  section  is used to specify some path names required by the
       server.  Some of these paths can also be set from the command line (see
       Xserver(1) and Xorg(1)).  The command line settings override the values
       specified in the config file.  The Files section is  optional,  as  are
       all of the entries that may appear in it.

       The entries that can appear in this section are:

       FontPath "path"
              sets  the search path for fonts.  This path is a comma separated
              list of font path elements which the Xorg  server  searches  for
              font databases.  Multiple FontPath entries may be specified, and
              they will be concatenated to build up the fontpath used  by  the
              server.   Font  path  elements  may be either absolute directory
              paths, or a font server  identifier.   Font  server  identifiers
              have the form:

                  &lt;trans&gt;/&lt;hostname&gt;:&lt;port-number&gt;

              where  &lt;trans&gt;  is  the  transport type to use to connect to the
              font server (e.g., unix for UNIX-domain sockets  or  tcp  for  a
              TCP/IP  connection),  &lt;hostname&gt;  is the hostname of the machine
              running the font server, and &lt;port-number&gt; is  the  port  number
              that the font server is listening on (usually 7100).

              When  this entry is not specified in the config file, the server
              falls back to the compiled-in default font path, which  contains
              the following font path elements:

                  /usr/lib/X11/fonts/misc/
                  /usr/lib/X11/fonts/TTF/
                  /usr/lib/X11/fonts/Type1/
                  /usr/lib/X11/fonts/75dpi/
                  /usr/lib/X11/fonts/100dpi/

              The  recommended font path contains the following font path ele-
              ments:

                  /usr/lib/X11/fonts/local/
                  /usr/lib/X11/fonts/misc/
                  /usr/lib/X11/fonts/75dpi/:unscaled
                  /usr/lib/X11/fonts/100dpi/:unscaled
                  /usr/lib/X11/fonts/Type1/
                  /usr/lib/X11/fonts/Speedo/
                  /usr/lib/X11/fonts/75dpi/
                  /usr/lib/X11/fonts/100dpi/

              Font path elements that are found to be invalid are removed from
              the font path when the server starts up.

       RGBPath "path"
              sets  the path name for the RGB color database.  When this entry
              is not specified in the config file, the server  falls  back  to
              the compiled-in default RGB path, which is:

                  /usr/share/X11/rgb

       Note that an implicit .txt is added to this path if the server was com-
       piled to use text rather than binary format RGB color databases.

       ModulePath "path"
              sets the search path for loadable  Xorg  server  modules.   This
              path  is  a  comma  separated list of directories which the Xorg
              server searches for loadable modules loading in the order speci-
              fied.   Multiple  ModulePath  entries may be specified, and they
              will be concatenated to build the module search path used by the
              server.

SERVERFLAGS SECTION
       In  addition to options specific to this section (described below), the
       ServerFlags section is used to specify some global Xorg server options.
       All  of  the entries in this section are Options, although for compati-
       bility purposes some of the old style  entries  are  still  recognised.
       Those old style entries are not documented here, and using them is dis-
       couraged.  The ServerFlags section is optional, as are the entries that
       may be specified in it.

       Options  specified in this section (with the exception of the "Default-
       ServerLayout" Option) may be overridden by  Options  specified  in  the
       active ServerLayout section.  Options with command line equivalents are
       overridden when their command line equivalent  is  used.   The  options
       recognised by this section are:

       Option "DefaultServerLayout"  "layout-id"
              This  specifies  the  default ServerLayout section to use in the
              absence of the -layout command line option.

       Option "NoTrapSignals"  "boolean"
              This prevents the Xorg server from trapping  a  range  of  unex-
              pected  fatal  signals  and  exiting cleanly.  Instead, the Xorg
              server will die and drop core where  the  fault  occurred.   The
              default  behaviour  is  for the Xorg server to exit cleanly, but
              still drop a core file.  In general you never want to  use  this
              option  unless you are debugging an Xorg server problem and know
              how to deal with the consequences.

       Option "DontVTSwitch"  "boolean"
              This disallows the use of the  Ctrl+Alt+Fn  sequence  (where  Fn
              refers  to one of the numbered function keys).  That sequence is
              normally used to switch to another "virtual terminal" on operat-
              ing  systems  that  have  this  feature.   When  this  option is
              enabled, that key sequence has no special meaning and is  passed
              to clients.  Default: off.

       Option "DontZap"  "boolean"
              This disallows the use of the Ctrl+Alt+Backspace sequence.  That
              sequence is normally used to terminate the  Xorg  server.   When
              this option is enabled, that key sequence has no special meaning
              and is passed to clients.  Default: off.

       Option "DontZoom"  "boolean"
              This  disallows  the  use  of   the   Ctrl+Alt+Keypad-Plus   and
              Ctrl+Alt+Keypad-Minus  sequences.  These sequences allows you to
              switch between video modes.  When this option is enabled,  those
              key sequences have no special meaning and are passed to clients.
              Default: off.

       Option "DisableVidModeExtension"  "boolean"
              This disables the parts of the VidMode  extension  used  by  the
              xvidtune  client  that  can  be  used to change the video modes.
              Default: the VidMode extension is enabled.

       Option "AllowNonLocalXvidtune"  "boolean"
              This allows the xvidtune client (and other clients that use  the
              VidMode extension) to connect from another host.  Default: off.

       Option "DisableModInDev"  "boolean"
              This  disables  the parts of the Xorg-Misc extension that can be
              used to modify the input device settings dynamically.   Default:
              that functionality is enabled.

       Option "AllowNonLocalModInDev"  "boolean"
              This  allows  a  client  to connect from another host and change
              keyboard and mouse settings in  the  running  server.   Default:
              off.

       Option "AllowMouseOpenFail"  "boolean"
              This  allows  the  server  to  start up even if the mouse device
              can't be opened/initialised.  Default: false.

       Option "VTInit"  "command"
              Runs command after the VT used by the server  has  been  opened.
              The  command  string  is passed to "/bin/sh -c", and is run with
              the real user's id with stdin and stdout set  to  the  VT.   The
              purpose of this option is to allow system dependent VT initiali-
              sation commands to be run.  This option should rarely be needed.
              Default: not set.

       Option "VTSysReq"  "boolean"
              enables  the  SYSV-style VT switch sequence for non-SYSV systems
              which support VT switching.  This sequence is Alt-SysRq followed
              by  a function key (Fn).  This prevents the Xorg server trapping
              the keys used for the default VT switch  sequence,  which  means
              that clients can access them.  Default: off.

       Option "XkbDisable" "boolean"
              disable/enable  the  XKEYBOARD  extension.  The -kb command line
              option overrides this  config  file  option.   Default:  XKB  is
              enabled.

       Option "BlankTime"  "time"
              sets  the  inactivity timeout for the blank phase of the screen-
              saver.  time is in minutes.  This  is  equivalent  to  the  Xorg
              server's  -s flag, and the value can be changed at run-time with
              xset(1).  Default: 10 minutes.

       Option "StandbyTime"  "time"
              sets the inactivity timeout for the standby phase of DPMS  mode.
              time  is  in  minutes,  and the value can be changed at run-time
              with xset(1).  Default: 20 minutes.  This is only  suitable  for
              VESA  DPMS  compatible monitors, and may not be supported by all
              video drivers.  It is only enabled for  screens  that  have  the
              "DPMS" option set (see the MONITOR section below).

       Option "SuspendTime"  "time"
              sets  the inactivity timeout for the suspend phase of DPMS mode.
              time is in minutes, and the value can  be  changed  at  run-time
              with  xset(1).   Default: 30 minutes.  This is only suitable for
              VESA DPMS compatible monitors, and may not be supported  by  all
              video  drivers.   It  is  only enabled for screens that have the
              "DPMS" option set (see the MONITOR section below).

       Option "OffTime"  "time"
              sets the inactivity timeout for the  off  phase  of  DPMS  mode.
              time  is  in  minutes,  and the value can be changed at run-time
              with xset(1).  Default: 40 minutes.  This is only  suitable  for
              VESA  DPMS  compatible monitors, and may not be supported by all
              video drivers.  It is only enabled for  screens  that  have  the
              "DPMS" option set (see the MONITOR section below).

       Option "Pixmap"  "bpp"
              This sets the pixmap format to use for depth 24.  Allowed values
              for bpp are 24 and 32.  Default: 32  unless  driver  constraints
              don't  allow  this  (which  is  rare).  Note: some clients don't
              behave well when this value is set to 24.

       Option "PC98"  "boolean"
              Specify that the machine is  a  Japanese  PC-98  machine.   This
              should  not be enabled for anything other than the Japanese-spe-
              cific PC-98 architecture.  Default: auto-detected.

       Option "NoPM"  "boolean"
              Disables something to do with power management events.  Default:
              PM enabled on platforms that support it.

       Option "Xinerama"  "boolean"
              enable or disable XINERAMA extension.  Default is disabled.

       Option "AllowDeactivateGrabs" "boolean"
              This  option  enables  the use of the Ctrl+Alt+Keypad-Divide key
              sequence to deactivate any  active  keyboard  and  mouse  grabs.
              Default: off.

       Option "AllowClosedownGrabs" "boolean"
              This  option enables the use of the Ctrl+Alt+Keypad-Multiply key
              sequence to kill clients with an active keyboard or  mouse  grab
              as  well  as  killing  any  application that may have locked the
              server,  normally  using  the  XGrabServer(3)   Xlib   function.
              Default: off.
              Note  that  the options AllowDeactivateGrabs and AllowClosedown-
              Grabs will allow  users  to  remove  the  grab  used  by  screen
              saver/locker  programs.   An  API was written to such cases.  If
              you enable this option, make sure your  screen  saver/locker  is
              updated.  Default: off.

       Option "HandleSpecialKeys" "when"
              This option controls when the server uses the builtin handler to
              process special key combinations (such  as  Ctrl+Alt+Backspace).
              Normally  the  XKEYBOARD extension keymaps will provide mappings
              for each of the special key combinations, so the builtin handler
              is  not  needed unless the XKEYBOARD extension is disabled.  The
              value of when can be Always, Never, or WhenNeeded.  Default: Use
              the  builtin  handler  only if needed.  The server will scan the
              keymap for a mapping to the Terminate action and, if found,  use
              XKEYBOARD  for processing actions, otherwise the builtin handler
              will be used.

       Option "AIGLX" "boolean"
              enable or disable AIGLX. AIGLX is enabled by default.

       Option "UseDefaultFontPath" "boolean"
              Include the default font path even if other paths are  specified
              in xorg.conf. If enabled, other font paths are included as well.
              Enabled by default.

       Option "IgnoreABI" "boolean"
              Allow modules built for a  different,  potentially  incompatible
              version of the X server to load. Disabled by default.

MODULE SECTION
       The  Module section is used to specify which Xorg server modules should
       be loaded.  This section is ignored when the Xorg server  is  built  in
       static  form.  The types of modules normally loaded in this section are
       Xorg server extension modules, and font rasteriser modules.  Most other
       module  types  are  loaded automatically when they are needed via other
       mechanisms.  The Module section is optional, as are all of the  entries
       that may be specified in it.

       Entries  in  this section may be in two forms.  The first and most com-
       monly used form is an entry that uses the Load  keyword,  as  described
       here:

       Load  "modulename"
              This  instructs the server to load the module called modulename.
              The module name given should be the module's standard name,  not
              the  module file name.  The standard name is case-sensitive, and
              does not include the "lib" prefix, or the ".a", ".o",  or  ".so"
              suffixes.

              Example:  the  FreeType  font  rasteriser can be loaded with the
              following entry:

                  Load "freetype"

       Disable  "modulename"
              This instructs the server to not load the module called  module-
              name.   Some  modules  are  loaded by default in the server, and
              this overrides that default. If a Load instruction is given  for
              the  same  module,  it overrides the Disable instruction and the
              module is loaded. The module name given should be  the  module's
              standard  name,  not  the  module  file  name.  As with the Load
              instruction, the standard name is case-sensitive, and  does  not
              include the "lib" prefix, or the ".a", ".o", or ".so" suffixes.

       The  second  form  of  entry  is a SubSection, with the subsection name
       being the module name, and the contents of the SubSection being Options
       that are passed to the module when it is loaded.

       Example:  the  extmod  module  (which contains a miscellaneous group of
       server extensions) can be loaded, with the XFree86-DGA  extension  dis-
       abled by using the following entry:

           SubSection "extmod"
              Option  "omit XFree86-DGA"
           EndSubSection

       Modules  are searched for in each directory specified in the ModulePath
       search path, and in the drivers, input, extensions, fonts, and internal
       subdirectories  of  each  of  those  directories.  In addition to this,
       operating system specific subdirectories of all the above are  searched
       first if they exist.

       To  see  what  font and extension modules are available, check the con-
       tents of the following directories:

           /usr/lib/modules/fonts
           /usr/lib/modules/extensions

       The "bitmap" font module is loaded automatically.   It  is  recommended
       that  at  very  least  the  "extmod" extension module be loaded.  If it
       isn't, some commonly used server extensions (like the SHAPE  extension)
       will not be available.

INPUTDEVICE SECTION
       The  config  file  may  have multiple InputDevice sections.  There will
       normally be at least two: one for the core (primary) keyboard, and  one
       of the core pointer.  If either of these two is missing, a default con-
       figuration for the missing ones will be used.   Currently  the  default
       configuration may not work as expected on all platforms.

       InputDevice sections have the following format:

           Section "InputDevice"
               Identifier "name"
               Driver     "inputdriver"
               options
               ...
           EndSection

       The  Identifier and Driver entries are required in all InputDevice sec-
       tions.  All other entries are optional.

       The Identifier entry specifies the unique name for this  input  device.
       The Driver entry specifies the name of the driver to use for this input
       device.  When using  the  loadable  server,  the  input  driver  module
       "inputdriver"  will  be loaded for each active InputDevice section.  An
       InputDevice section is considered active if  it  is  referenced  by  an
       active  ServerLayout  section,  if it is referenced by the -keyboard or
       -pointer command line options, or if it is selected implicitly  as  the
       core  pointer or keyboard device in the absence of such explicit refer-
       ences.  The most  commonly  used  input  drivers  are  keyboard(4)  and
       mouse(4).

       In  the absence of an explicitly specified core input device, the first
       InputDevice marked as CorePointer (or CoreKeyboard) is used.  If  there
       is  no  match  there,  the  first InputDevice that uses the "mouse" (or
       "keyboard" or "kbd") driver is used.  The  final  fallback  is  to  use
       built-in default configurations.

       InputDevice  sections  recognise some driver-independent Options, which
       are described here.  See the individual input driver manual pages for a
       description of the device-specific options.

       Option "CorePointer"
              When  this  is  set,  the  input device is installed as the core
              (primary) pointer  device.   There  must  be  exactly  one  core
              pointer.  If this option is not set here, or in the ServerLayout
              section, or from the -pointer  command  line  option,  then  the
              first  input  device  that  is  capable  of being used as a core
              pointer will be selected as the core pointer.   This  option  is
              implicitly set when the obsolete Pointer section is used.

       Option "CoreKeyboard"
              When  this  is  set,  the input device is to be installed as the
              core (primary) keyboard device.  There must be exactly one  core
              keyboard.   If  this option is not set here, in the ServerLayout
              section, or from the -keyboard command  line  option,  then  the
              first  input device that is capable of being used as a core key-
              board will be selected as the core  keyboard.   This  option  is
              implicitly set when the obsolete Keyboard section is used.

       Option "AlwaysCore"  "boolean"

       Option "SendCoreEvents"  "boolean"
              Both of these options are equivalent, and when enabled cause the
              input device to always report core events.  This  can  be  used,
              for  example,  to allow an additional pointer device to generate
              core pointer events (like moving the cursor, etc).

       Option "HistorySize"  "number"
           Sets the motion history size.  Default: 0.

       Option "SendDragEvents"  "boolean"
              ???

DEVICE SECTION
       The config file may have multiple Device sections.  There  must  be  at
       least one, for the video card being used.

       Device sections have the following format:

           Section "Device"
               Identifier "name"
               Driver     "driver"
               entries
               ...
           EndSection

       The  Identifier and Driver entries are required in all Device sections.
       All other entries are optional.

       The Identifier entry  specifies  the  unique  name  for  this  graphics
       device.   The  Driver entry specifies the name of the driver to use for
       this graphics device.  When using the loadable server, the driver  mod-
       ule  "driver"  will be loaded for each active Device section.  A Device
       section is considered active if it is referenced by  an  active  Screen
       section.

       Device  sections recognise some driver-independent entries and Options,
       which  are  described  here.   Not  all  drivers  make  use  of   these
       driver-independent  entries,  and  many  of those that do don't require
       them to be specified because the information is auto-detected.  See the
       individual  graphics  driver manual pages for further information about
       this, and for a description of the device-specific options.  Note  that
       most  of  the  Options  listed  here (but not the other entries) may be
       specified in the Screen section instead of here in the Device section.

       BusID  "bus-id"
              This specifies the bus  location  of  the  graphics  card.   For
              PCI/AGP    cards,    the    bus-id    string    has   the   form
              PCI:bus:device:function (e.g., "PCI:1:0:0" might be  appropriate
              for an AGP card).  This field is usually optional in single-head
              configurations when using the primary graphics card.  In  multi-
              head  configurations, or when using a secondary graphics card in
              a single-head configuration, this entry is mandatory.  Its  main
              purpose  is to make an unambiguous connection between the device
              section and the hardware it is representing.   This  information
              can  usually be found by running the Xorg server with the -scan-
              pci command line option.

       Screen  number
              This option is mandatory for cards where a single PCI entity can
              drive more than one display (i.e., multiple CRTCs sharing a sin-
              gle graphics accelerator and video memory).  One Device  section
              is  required  for each head, and this parameter determines which
              head each of the Device sections applies to.  The  legal  values
              of  number  range  from  0  to one less than the total number of
              heads per entity.  Most drivers require that the primary  screen
              (0) be present.

       Chipset  "chipset"
              This  usually  optional  entry specifies the chipset used on the
              graphics board.  In  most  cases  this  entry  is  not  required
              because  the  drivers  will  probe the hardware to determine the
              chipset type.  Don't specify it unless the driver-specific docu-
              mentation recommends that you do.

       Ramdac  "ramdac-type"
              This  optional  entry  specifies  the type of RAMDAC used on the
              graphics board.  This is only used by a few of the drivers,  and
              in  most cases it is not required because the drivers will probe
              the hardware to determine the RAMDAC type where possible.  Don't
              specify  it  unless the driver-specific documentation recommends
              that you do.

       DacSpeed  speed

       DacSpeed  speed-8 speed-16 speed-24 speed-32
              This optional entry specifies the RAMDAC speed rating (which  is
              usually printed on the RAMDAC chip).  The speed is in MHz.  When
              one value is given, it applies to all framebuffer  pixel  sizes.
              When  multiple  values  are given, they apply to the framebuffer
              pixel sizes 8, 16, 24 and 32 respectively.  This is not used  by
              many drivers, and only needs to be specified when the speed rat-
              ing of the RAMDAC is different from the  defaults  built  in  to
              driver,  or  when  the  driver  can't  auto-detect  the  correct
              defaults.  Don't specify it unless the driver-specific  documen-
              tation recommends that you do.

       Clocks  clock ...
              specifies the pixel that are on your graphics board.  The clocks
              are in MHz, and may be specified as  a  floating  point  number.
              The value is stored internally to the nearest kHz.  The ordering
              of the clocks is important.  It must match the  order  in  which
              they  are selected on the graphics board.  Multiple Clocks lines
              may be specified, and each is concatenated  to  form  the  list.
              Most  drivers do not use this entry, and it is only required for
              some older boards with non-programmable clocks.   Don't  specify
              this  entry  unless the driver-specific documentation explicitly
              recommends that you do.

       ClockChip  "clockchip-type"
              This optional entry is used to specify the clock  chip  type  on
              graphics boards which have a programmable clock generator.  Only
              a few  Xorg  drivers  support  programmable  clock  chips.   For
              details, see the appropriate driver manual page.

       VideoRam  mem
              This  optional  entry  specifies the amount of video ram that is
              installed on the graphics board.  This is  measured  in  kBytes.
              In  most  cases  this  is  not  required because the Xorg server
              probes the graphics  board  to  determine  this  quantity.   The
              driver-specific  documentation  should indicate when it might be
              needed.

       BiosBase  baseaddress
              This optional entry specifies the base address of the video BIOS
              for  the VGA board.  This address is normally auto-detected, and
              should only be specified if  the  driver-specific  documentation
              recommends it.

       MemBase  baseaddress
              This  optional  entry  specifies  the  memory  base address of a
              graphics board's linear frame buffer.  This entry is not used by
              many drivers, and it should only be specified if the driver-spe-
              cific documentation recommends it.

       IOBase  baseaddress
              This optional entry specifies the IO base address.   This  entry
              is  not used by many drivers, and it should only be specified if
              the driver-specific documentation recommends it.

       ChipID  id
              This optional entry specifies a numerical  ID  representing  the
              chip  type.   For  PCI cards, it is usually the device ID.  This
              can be used to override the auto-detection, but that should only
              be done when the driver-specific documentation recommends it.

       ChipRev  rev
              This  optional  entry  specifies the chip revision number.  This
              can be used to override the auto-detection, but that should only
              be done when the driver-specific documentation recommends it.

       TextClockFreq  freq
              This  optional entry specifies the pixel clock frequency that is
              used for the regular text mode.  The frequency is  specified  in
              MHz.  This is rarely used.

       Option "ModeDebug" "boolean"
              Enable  printing of additional debugging information about mode-
              setting to the server log.

       Options
              Option flags may be specified in  the  Device  sections.   These
              include  driver-specific options and driver-independent options.
              The former are described in the  driver-specific  documentation.
              Some  of the latter are described below in the section about the
              Screen section, and they may also be included here.


VIDEOADAPTOR SECTION
       Nobody wants to say how this works.  Maybe nobody knows ...


MONITOR SECTION
       The config file may have multiple Monitor sections.  There should  nor-
       mally  be  at least one, for the monitor being used, but a default con-
       figuration will be created when one isn't specified.

       Monitor sections have the following format:

           Section "Monitor"
               Identifier "name"
               entries
               ...
           EndSection

       The only mandatory entry in a Monitor section is the Identifier entry.

       The Identifier entry specifies the unique name for this  monitor.   The
       Monitor section may be used to provide information about the specifica-
       tions of the monitor, monitor-specific Options, and  information  about
       the video modes to use with the monitor.

       With  RandR  1.2-enabled  drivers, monitor sections may be tied to spe-
       cific outputs of the video card.  Using the name of the output  defined
       by the video driver plus the identifier of a monitor section, one asso-
       ciates a monitor section with an output by  adding  an  option  to  the
       Device section in the following format:

       Option "Monitor-outputname" "monitorsection"

       (for example, Option "Monitor-VGA" "VGA monitor" for a VGA output)

       In  the absence of specific association of monitor sections to outputs,
       if a monitor section is present the server will associate  it  with  an
       output  to  preserve  compatibility for previous single-head configura-
       tions.

       Specifying video modes is optional because the server will use the  DDC
       or other information provided by the monitor to automatically configure
       the list of modes available.  When modes are  specified  explicitly  in
       the  Monitor  section (with the Modes, ModeLine, or UseModes keywords),
       built-in modes with the same names are not  included.   Built-in  modes
       with different names are, however, still implicitly included, when they
       meet the requirements of the monitor.

       The entries that may be used in Monitor sections are described below.

       VendorName  "vendor"
              This optional entry specifies the monitor's manufacturer.

       ModelName  "model"
              This optional entry specifies the monitor's model.

       HorizSync  horizsync-range
              gives the range(s) of horizontal sync frequencies  supported  by
              the  monitor.   horizsync-range may be a comma separated list of
              either discrete values or ranges of values.  A range  of  values
              is two values separated by a dash.  By default the values are in
              units of kHz.  They may be specified in MHz or Hz if MHz  or  Hz
              is added to the end of the line.  The data given here is used by
              the Xorg server to determine if video modes are within the spec-
              ifications of the monitor.  This information should be available
              in the monitor's handbook.  If this entry is omitted, a  default
              range of 28-33kHz is used.

       VertRefresh  vertrefresh-range
              gives  the range(s) of vertical refresh frequencies supported by
              the monitor.  vertrefresh-range may be a comma separated list of
              either  discrete  values or ranges of values.  A range of values
              is two values separated by a dash.  By default the values are in
              units  of Hz.  They may be specified in MHz or kHz if MHz or kHz
              is added to the end of the line.  The data given here is used by
              the Xorg server to determine if video modes are within the spec-
              ifications of the monitor.  This information should be available
              in  the monitor's handbook.  If this entry is omitted, a default
              range of 43-72Hz is used.

       DisplaySize  width height
              This optional entry gives the width and height, in  millimetres,
              of  the  picture  area of the monitor.  If given this is used to
              calculate the horizontal and vertical pitch (DPI) of the screen.

       Gamma  gamma-value

       Gamma  red-gamma green-gamma blue-gamma
              This is an optional entry that can be used to specify the  gamma
              correction  for  the  monitor.   It may be specified as either a
              single value or as three separate RGB values.  The values should
              be  in  the  range 0.1 to 10.0, and the default is 1.0.  Not all
              drivers are capable of using this information.

       UseModes  "modesection-id"
              Include the set of modes listed in the Modes section called mod-
              esection-id.   This  makes all of the modes defined in that sec-
              tion available for use by this monitor.

       Mode  "name"
              This is an optional multi-line entry that can be used to provide
              definitions for video modes for the monitor.  In most cases this
              isn't necessary because the built-in set of VESA standard  modes
              will  be  sufficient.  The Mode keyword indicates the start of a
              multi-line video mode description.  The mode description is ter-
              minated with the EndMode keyword.  The mode description consists
              of the following entries:

              DotClock  clock
                  is the dot (pixel) clock rate to be used for the mode.

              HTimings  hdisp hsyncstart hsyncend htotal
                  specifies the horizontal timings for the mode.

              VTimings  vdisp vsyncstart vsyncend vtotal
                  specifies the vertical timings for the mode.

              Flags  "flag" ...
                  specifies an optional set of mode flags, each of which is  a
                  separate  string  in  double  quotes.  "Interlace" indicates
                  that the mode is interlaced.  "DoubleScan" indicates a  mode
                  where  each  scanline is doubled.  "+HSync" and "-HSync" can
                  be  used  to  select  the  polarity  of  the  HSync  signal.
                  "+VSync"  and "-VSync" can be used to select the polarity of
                  the VSync signal.  "Composite" can be used to  specify  com-
                  posite  sync on hardware where this is supported.  Addition-
                  ally, on some hardware, "+CSync" and "-CSync" may be used to
                  select the composite sync polarity.

              HSkew  hskew
                  specifies  the  number  of pixels (towards the right edge of
                  the screen) by which the display  enable  signal  is  to  be
                  skewed.   Not all drivers use this information.  This option
                  might become necessary to override the  default  value  sup-
                  plied  by  the  server  (if any).  "Roving" horizontal lines
                  indicate this value needs to be increased.  If the last  few
                  pixels on a scan line appear on the left of the screen, this
                  value should be decreased.

              VScan  vscan
                  specifies the number of times each scanline  is  painted  on
                  the  screen.   Not all drivers use this information.  Values
                  less than 1 are treated as 1, which is the default.   Gener-
                  ally,  the  "DoubleScan"  Flag  mentioned above doubles this
                  value.

       ModeLine  "name" mode-description
              This entry is a more compact version of the Mode entry,  and  it
              also  can  be used to specify video modes for the monitor.  is a
              single line format for specifying video modes.   In  most  cases
              this  isn't  necessary because the built-in set of VESA standard
              modes will be sufficient.

              The mode-description is in four sections,  the  first  three  of
              which  are mandatory.  The first is the dot (pixel) clock.  This
              is a single number specifying the pixel clock rate for the  mode
              in MHz.  The second section is a list of four numbers specifying
              the horizontal timings.  These numbers  are  the  hdisp,  hsync-
              start, hsyncend, and htotal values.  The third section is a list
              of four numbers specifying the vertical timings.  These  numbers
              are  the  vdisp,  vsyncstart,  vsyncend, and vtotal values.  The
              final section is a list of flags specifying  other  characteris-
              tics  of  the mode.  Interlace indicates that the mode is inter-
              laced.  DoubleScan indicates a mode where each scanline is  dou-
              bled.   +HSync  and -HSync can be used to select the polarity of
              the HSync signal.  +VSync and -VSync can be used to  select  the
              polarity  of the VSync signal.  Composite can be used to specify
              composite sync on hardware where this is  supported.   Addition-
              ally,  on some hardware, +CSync and -CSync may be used to select
              the composite sync polarity.  The HSkew and VScan  options  men-
              tioned  above  in  the  Modes entry description can also be used
              here.

       Option "DPMS"  "bool"
              This option controls whether the server should enable  the  DPMS
              extension  for power management for this screen.  The default is
              to enable the extension.

       Option "SyncOnGreen"  "bool"
              This option controls whether the video  card  should  drive  the
              sync  signal on the green color pin.  Not all cards support this
              option, and most monitors do not require  it.   The  default  is
              off.

       Option "TargetRefresh"  "rate"
              This optional entry specifies the vertical refresh rate that the
              server should aim for when selecting video modes.  Without  this
              option,  the  default  is  to  prefer  modes with higher refresh
              rates.

       Option "PreferredMode"  "string"
              This optional entry specifies a mode to be marked  as  the  pre-
              ferred initial mode of the monitor.  (RandR 1.2-supporting driv-
              ers only)

       Option "Position"  "x y"
              This optional entry specifies the position of the monitor within
              the X screen.  (RandR 1.2-supporting drivers only)

       Option "LeftOf"  "monitor"
              This  optional  entry specifies that the monitor should be posi-
              tioned to the left of the monitor of  the  given  name.   (RandR
              1.2-supporting drivers only)

       Option "RightOf"  "monitor"
              This  optional  entry specifies that the monitor should be posi-
              tioned to the right of the monitor of the  given  name.   (RandR
              1.2-supporting drivers only)

       Option "Above"  "monitor"
              This  optional  entry specifies that the monitor should be posi-
              tioned above the monitor of the given name.  (RandR 1.2-support-
              ing drivers only)

       Option "Below"  "monitor"
              This  optional  entry specifies that the monitor should be posi-
              tioned below the monitor of the given name.  (RandR 1.2-support-
              ing drivers only)

       Option "Enable"  "bool"
              This  optional  entry  specifies  whether  the monitor should be
              turned on at startup.  By default, the server  will  attempt  to
              enable  all  connected  monitors.  (RandR 1.2-supporting drivers
              only)

       Option "MinClock"  "frequency"
              This optional entry specifies the minimum  dot  clock,  in  kHz,
              that is supported by the monitor.

       Option "MaxClock"  "frequency"
              This  optional  entry  specifies  the maximum dot clock, in kHz,
              that is supported by the monitor.

       Option "Ignore"  "bool"
              This optional entry specifies that the monitor should be ignored
              entirely, and not reported through RandR.  This is useful if the
              hardware reports the  presence  of  outputs  that  don't  exist.
              (RandR 1.2-supporting drivers only)

       Option "Rotate"  "rotation"
              This  optional entry specifies the initial rotation of the given
              monitor.   Valid  values  for  rotation  are  "normal",  "left",
              "right", and "inverted".  (RandR 1.2-supporting drivers only)


MODES SECTION
       The  config file may have multiple Modes sections, or none.  These sec-
       tions provide a way of defining sets of video  modes  independently  of
       the  Monitor  sections.   Monitor  sections may include the definitions
       provided in these sections by using  the  UseModes  keyword.   In  most
       cases  the Modes sections are not necessary because the built-in set of
       VESA standard modes will be sufficient.

       Modes sections have the following format:

           Section "Modes"
               Identifier "name"
               entries
               ...
           EndSection

       The Identifier entry specifies the unique name for  this  set  of  mode
       descriptions.   The  other  entries permitted in Modes sections are the
       Mode and ModeLine entries that are described above in the Monitor  sec-
       tion.

SCREEN SECTION
       The  config  file  may have multiple Screen sections.  There must be at
       least one, for the "screen" being  used.   A  "screen"  represents  the
       binding  of  a  graphics device (Device section) and a monitor (Monitor
       section).  A Screen section is considered "active" if it is  referenced
       by  an  active  ServerLayout  section  or  by  the -screen command line
       option.  If neither of those is present, the first Screen section found
       in the config file is considered the active one.

       Screen sections have the following format:

           Section "Screen"
               Identifier "name"
               Device     "devid"
               Monitor    "monid"
               entries
               ...
               SubSection "Display"
                  entries
                  ...
               EndSubSection
               ...
           EndSection

       The  Identifier  and  Device  entries  are  mandatory.   All others are
       optional.

       The Identifier entry specifies the unique name for  this  screen.   The
       Screen  section  provides  information  specific  to  the whole screen,
       including screen-specific Options.  In multi-head configurations, there
       will  be  multiple  active  Screen  sections,  one  for each head.  The
       entries available for this section are:

       Device  "device-id"
              This mandatory entry specifies the Device section to be used for
              this  screen.   This  is what ties a specific graphics card to a
              screen.  The device-id must match the  Identifier  of  a  Device
              section in the config file.

       Monitor  "monitor-id"
              specifies  which  monitor  description  is  to  be used for this
              screen.  If a Monitor name is not specified, a default  configu-
              ration  is  used.   Currently  the default configuration may not
              function as expected on all platforms.

       VideoAdaptor  "xv-id"
              specifies an optional Xv video adaptor description  to  be  used
              with this screen.

       DefaultDepth  depth
              specifies  which  color  depth the server should use by default.
              The -depth command line option can be used to override this.  If
              neither  is specified, the default depth is driver-specific, but
              in most cases is 8.

       DefaultFbBpp  bpp
              specifies which framebuffer  layout  to  use  by  default.   The
              -fbbpp  command  line  option  can be used to override this.  In
              most cases the driver will chose  the  best  default  value  for
              this.   The only case where there is even a choice in this value
              is for depth 24, where some hardware supports both a  packed  24
              bit framebuffer layout and a sparse 32 bit framebuffer layout.

       Options
              Various  Option  flags  may  be specified in the Screen section.
              Some are driver-specific and are described in the  driver  docu-
              mentation.   Others  are driver-independent, and will eventually
              be described here.

       Option "Accel"
              Enables XAA (X  Acceleration  Architecture),  a  mechanism  that
              makes  video  cards'  2D  hardware acceleration available to the
              __xservername__ server.  This option is on by  default,  but  it
              may be necessary to turn it off if there are bugs in the driver.
              There are many options to disable  specific  accelerated  opera-
              tions, listed below.  Note that disabling an operation will have
              no effect if the operation is not accelerated  (whether  due  to
              lack of support in the hardware or in the driver).

       Option "InitPrimary" "boolean"
              Use  the  Int10  module to initialize the primary graphics card.
              Normally, only secondary cards are soft-booted using  the  Int10
              module,  as the primary card has already been initialized by the
              BIOS at boot time.  Default: false.

       Option "NoInt10" "boolean"
              Disables the Int10 module, a module that uses the int10 call  to
              the BIOS of the graphics card to initialize it.  Default: false.

       Option "NoMTRR"
              Disables MTRR (Memory Type Range Register) support, a feature of
              modern processors which can improve video performance by a  fac-
              tor  of  up  to  2.5.  Some hardware has buggy MTRR support, and
              some video drivers have been  known  to  exhibit  problems  when
              MTRR's are used.

       Option "XaaNoCPUToScreenColorExpandFill"
              Disables  accelerated  rectangular  expansion  blits from source
              patterns stored in system memory (using  a  memory-mapped  aper-
              ture).

       Option "XaaNoColor8x8PatternFillRect"
              Disables  accelerated  fills  of  a  rectangular  region  with a
              full-color pattern.

       Option "XaaNoColor8x8PatternFillTrap"
              Disables accelerated  fills  of  a  trapezoidal  region  with  a
              full-color pattern.

       Option "XaaNoDashedBresenhamLine"
              Disables accelerated dashed Bresenham line draws.

       Option "XaaNoDashedTwoPointLine"
              Disables  accelerated  dashed  line  draws between two arbitrary
              points.

       Option "XaaNoImageWriteRect"
              Disables accelerated transfers of  full-color  rectangular  pat-
              terns  from system memory to video memory (using a memory-mapped
              aperture).

       Option "XaaNoMono8x8PatternFillRect"
              Disables accelerated fills of a rectangular region with a  mono-
              chrome pattern.

       Option "XaaNoMono8x8PatternFillTrap"
              Disables  accelerated fills of a trapezoidal region with a mono-
              chrome pattern.

       Option "XaaOffscreenPixmaps"
              Enables accelerated draws into pixmaps stored in offscreen video
              memory.

       Option "XaaNoPixmapCache"
              Disables caching of patterns in offscreen video memory.

       Option "XaaNoScanlineCPUToScreenColorExpandFill"
              Disables  accelerated  rectangular  expansion  blits from source
              patterns stored in system memory (one scan line at a time).

       Option "XaaNoScanlineImageWriteRect"
              Disables accelerated transfers of  full-color  rectangular  pat-
              terns  from  system  memory  to video memory (one scan line at a
              time).

       Option "XaaNoScreenToScreenColorExpandFill"
              Disables accelerated rectangular  expansion  blits  from  source
              patterns stored in offscreen video memory.

       Option "XaaNoScreenToScreenCopy"
              Disables accelerated copies of rectangular regions from one part
              of video memory to another part of video memory.

       Option "XaaNoSolidBresenhamLine"
              Disables accelerated solid Bresenham line draws.

       Option "XaaNoSolidFillRect"
              Disables accelerated solid-color fills of rectangles.

       Option "XaaNoSolidFillTrap"
              Disables accelerated solid-color fills of Bresenham trapezoids.

       Option "XaaNoSolidHorVertLine"
              Disables accelerated solid horizontal and vertical line draws.

       Option "XaaNoSolidTwoPointLine"
              Disables accelerated solid  line  draws  between  two  arbitrary
              points.

       Each  Screen section may optionally contain one or more Display subsec-
       tions.  Those subsections provide  depth/fbbpp  specific  configuration
       information,  and the one chosen depends on the depth and/or fbbpp that
       is being used  for  the  screen.   The  Display  subsection  format  is
       described in the section below.


DISPLAY SUBSECTION
       Each  Screen  section  may  have  multiple  Display  subsections.   The
       "active" Display subsection is the first that matches the depth  and/or
       fbbpp  values being used, or failing that, the first that has neither a
       depth or fbbpp value specified.  The Display subsections are  optional.
       When  there  isn't one that matches the depth and/or fbbpp values being
       used, all the parameters that can be specified here fall back to  their
       defaults.

       Display subsections have the following format:

               SubSection "Display"
                   Depth  depth
                   entries
                   ...
               EndSubSection

       Depth  depth
              This entry specifies what colour depth the Display subsection is
              to be used for.  This entry is usually specified, but it may  be
              omitted to create a match-all Display subsection or when wishing
              to match only against the FbBpp parameter.  The range  of  depth
              values  that  are  allowed  depends on the driver.  Most drivers
              support 8, 15, 16 and 24.  Some also support  1  and/or  4,  and
              some  may support other values (like 30).  Note: depth means the
              number of bits in a pixel that are actually  used  to  determine
              the pixel colour.  32 is not a valid depth value.  Most hardware
              that uses 32 bits per pixel only uses 24 of  them  to  hold  the
              colour information, which means that the colour depth is 24, not
              32.

       FbBpp  bpp
              This entry specifies the framebuffer format this Display subsec-
              tion  is to be used for.  This entry is only needed when provid-
              ing depth 24 configurations that allow a choice between a 24 bpp
              packed framebuffer format and a 32bpp sparse framebuffer format.
              In most cases this entry should not be used.

       Weight  red-weight green-weight blue-weight
              This optional entry specifies the relative RGB weighting  to  be
              used  for  a  screen  is being used at depth 16 for drivers that
              allow multiple formats.  This may also  be  specified  from  the
              command line with the -weight option (see Xorg(1)).

       Virtual  xdim ydim
              This  optional  entry specifies the virtual screen resolution to
              be used.  xdim must be a multiple of either 8  or  16  for  most
              drivers,  and  a multiple of 32 when running in monochrome mode.
              The given value will be rounded down if this is  not  the  case.
              Video  modes  which are too large for the specified virtual size
              will be rejected.  If this entry is  not  present,  the  virtual
              screen resolution will be set to accommodate all the valid video
              modes given in the Modes entry.  Some drivers/hardware  combina-
              tions  do not support virtual screens.  Refer to the appropriate
              driver-specific documentation for details.

       ViewPort  x0 y0
              This optional entry sets the upper left corner  of  the  initial
              display.   This is only relevant when the virtual screen resolu-
              tion is different from the resolution of the initial video mode.
              If  this  entry  is  not given, then the initial display will be
              centered in the virtual display area.

       Modes  "mode-name" ...
              This optional entry specifies the list of video  modes  to  use.
              Each  mode-name  specified  must be in double quotes.  They must
              correspond to those specified or referenced in  the  appropriate
              Monitor  section  (including implicitly referenced built-in VESA
              standard modes).  The server will delete modes  from  this  list
              which  don't satisfy various requirements.  The first valid mode
              in this list will be the default display mode for startup.   The
              list  of  valid  modes  is  converted internally into a circular
              list.   It  is  possible  to  switch  to  the  next  mode   with
              Ctrl+Alt+Keypad-Plus and to the previous mode with Ctrl+Alt+Key-
              pad-Minus.  When this entry is omitted, the valid  modes  refer-
              enced  by  the appropriate Monitor section will be used.  If the
              Monitor section contains no modes, then the  selection  will  be
              taken from the built-in VESA standard modes.

       Visual  "visual-name"
              This optional entry sets the default root visual type.  This may
              also be specified from the command line (see the Xserver(1)  man
              page).   The  visual types available for depth 8 are (default is
              PseudoColor):

                  StaticGray
                  GrayScale
                  StaticColor
                  PseudoColor
                  TrueColor
                  DirectColor

              The visual type available for the  depths  15,  16  and  24  are
              (default is TrueColor):

                  TrueColor
                  DirectColor

              Not all drivers support DirectColor at these depths.

              The visual types available for the depth 4 are (default is Stat-
              icColor):

                  StaticGray
                  GrayScale
                  StaticColor
                  PseudoColor

              The visual type available for the depth 1 (monochrome) is  Stat-
              icGray.

       Black  red green blue
              This  optional  entry allows the "black" colour to be specified.
              This is only supported at depth 1.  The default is black.

       White  red green blue
              This optional entry allows the "white" colour to  be  specified.
              This is only supported at depth 1.  The default is white.

       Options
              Option flags may be specified in the Display subsections.  These
              may  include  driver-specific  options  and   driver-independent
              options.   The former are described in the driver-specific docu-
              mentation.  Some of the latter are described above in  the  sec-
              tion  about  the  Screen  section, and they may also be included
              here.

SERVERLAYOUT SECTION
       The config file may have multiple  ServerLayout  sections.   A  "server
       layout" represents the binding of one or more screens (Screen sections)
       and one or more input devices (InputDevice sections) to form a complete
       configuration.   In  multi-head  configurations,  it also specifies the
       relative layout of the heads.  A  ServerLayout  section  is  considered
       "active"  if  it is referenced by the -layout command line option or by
       an Option "DefaultServerLayout" entry in the ServerFlags  section  (the
       former  takes  precedence  over  the latter).  If those options are not
       used, the first ServerLayout section found in the config file  is  con-
       sidered  the  active one.  If no ServerLayout sections are present, the
       single active screen and two active (core) input devices  are  selected
       as described in the relevant sections above.

       ServerLayout sections have the following format:

           Section "ServerLayout"
               Identifier   "name"
               Screen       "screen-id"
               ...
               InputDevice  "idev-id"
               ...
               options
               ...
           EndSection

       Each  ServerLayout  section  must have an Identifier entry and at least
       one Screen entry.

       The Identifier entry specifies the unique name for this server  layout.
       The  ServerLayout  section  provides  information specific to the whole
       session, including session-specific Options.  The  ServerFlags  options
       (described  above)  may be specified here, and ones given here override
       those given in the ServerFlags section.

       The entries that may be used in this section are described here.

       Screen  screen-num "screen-id" position-information
              One of these entries must be given for each screen being used in
              a  session.  The screen-id field is mandatory, and specifies the
              Screen  section  being  referenced.   The  screen-num  field  is
              optional,  and  may  be  used  to  specify  the screen number in
              multi-head configurations.  When  this  field  is  omitted,  the
              screens  will  be numbered in the order that they are listed in.
              The numbering starts from 0, and must be consecutive.  The posi-
              tion-information  field  describes  the way multiple screens are
              positioned.  There are a number  of  different  ways  that  this
              information can be provided:

              x y

              Absolute  x y
                  These  both specify that the upper left corner's coordinates
                  are (x,y).  The Absolute keyword is  optional.   Some  older
                  versions of Xorg (4.2 and earlier) don't recognise the Abso-
                  lute keyword, so it's safest to just specify the coordinates
                  without it.

              RightOf   "screen-id"

              LeftOf    "screen-id"

              Above     "screen-id"

              Below     "screen-id"

              Relative  "screen-id" x y
                  These give the screen's location relative to another screen.
                  The first four position the screen immediately to the right,
                  left,  above or below the other screen.  When positioning to
                  the right or left, the top edges are  aligned.   When  posi-
                  tioning  above  or  below,  the left edges are aligned.  The
                  Relative form specifies the offset of  the  screen's  origin
                  (upper  left  corner)  relative  to  the  origin  of another
                  screen.

       InputDevice  "idev-id" "option" ...
              One of these entries should be given for each input device being
              used in a session.  Normally at least two are required, one each
              for the core pointer and keyboard devices.  If either  of  those
              is  missing, suitable InputDevice entries are searched for using
              the method described above  in  the  INPUTDEVICE  section.   The
              idev-id field is mandatory, and specifies the name of the Input-
              Device section being referenced.  Multiple option fields may  be
              specified,  each  in  double quotes.  The options permitted here
              are any that may also be  given  in  the  InputDevice  sections.
              Normally  only  session-specific  input  device options would be
              used here.  The most commonly used options are:

                  "CorePointer"
                  "CoreKeyboard"
                  "SendCoreEvents"

              and the first two should normally be used to indicate  the  core
              pointer and core keyboard devices respectively.

       Options
              In  addition  to  the  following,  any  option  permitted in the
              ServerFlags section may also be specified here.  When  the  same
              option  appears  in  both places, the value given here overrides
              the one given in the ServerFlags section.

       Option "IsolateDevice"  "bus-id"
              Restrict device resets to the specified bus-id.  See  the  BusID
              option  (described  in  DEVICE SECTION, above) for the format of
              the bus-id parameter.   This  option  overrides  SingleCard,  if
              specified.  At present, only PCI devices can be isolated in this
              manner.

       Option "SingleCard"  "boolean"
              As IsolateDevice, except that the bus ID of the first device  in
              the layout is used.

       Here is an example of a ServerLayout section for a dual headed configu-
       ration with two mice:

           Section "ServerLayout"
               Identifier  "Layout 1"
               Screen      "MGA 1"
               Screen      "MGA 2" RightOf "MGA 1"
               InputDevice "Keyboard 1" "CoreKeyboard"
               InputDevice "Mouse 1"    "CorePointer"
               InputDevice "Mouse 2"    "SendCoreEvents"
               Option      "BlankTime"  "5"
           EndSection

DRI SECTION
       This optional section is used  to  provide  some  information  for  the
       Direct Rendering Infrastructure.  Details about the format of this sec-
       tion can be found in the README.DRI document, which is  also  available
       on-line at &lt;http://dri.freedesktop.org/&gt;.

VENDOR SECTION
       The optional Vendor section may be used to provide vendor-specific con-
       figuration information.  Multiple Vendor sections may be  present,  and
       they  may  contain  an Identifier entry and multiple Option flags.  The
       data therein is not used in this release.

SEE ALSO
       General: X(7), Xserver(1), Xorg(1).

       Not all modules or interfaces are available on all platforms.

       Display  drivers:  apm(4),  chips(4),  cirrus(4),  cyrix(4),  fbdev(4),
       glide(4),  glint(4),  i128(4), i740(4), i810(4), imstt(4), mga(4), neo-
       magic(4), nv(4), r128(4), rendition(4), savage(4), s3virge(4), silicon-
       motion(4),   sis(4),   sunbw2(4),   suncg14(4),  suncg3(4),  suncg6(4),
       sunffb(4), sunleo(4), suntcx(4), tdfx(4), tga(4), trident(4), tseng(4),
       vesa(4), vga(4), via(4), vmware(4).

       Input  drivers: citron(4), dmc(4), dynapro(4), elographics(4), fpit(4),
       js_x(4), kbd(4), keyboard(4), microtouch(4), mouse(4), mutouch(4), pal-
       max(4), penmount(4), tek4957(4), void(4), wacom(4).

       Other modules and interfaces: fbdevhw(4), v4l(4).

AUTHORS
       This    manual    page   was   largely   rewritten   by   David   Dawes
       &lt;dawes@xfree86.org&gt;.



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