Понедельник (05/17/10)

/dev/pts/3
10:23:32
$PAGER=cat man 5 xorg.conf
xorg.conf(5)                                                      xorg.conf(5)
NAME
       xorg.conf - configuration File for Xorg X server
INTRODUCTION
       Xorg  supports several mechanisms for supplying/obtaining configuration
       and run-time parameters: command line options,  environment  variables,
       the   xorg.conf   configuration   file,  auto-detection,  and  fallback
       defaults.  When the same information is supplied in more than one  way,
       the  highest  precedence  mechanism is used.  The list of mechanisms is
       ordered from highest precedence to lowest.  Note that not  all  parame-
       ters  can  be  supplied  via  all  methods.  The available command line
       options and environment variables (and some defaults) are described  in
       the  Xserver(1)  and  Xorg(1)  manual  pages.   Most configuration file
       parameters, with their defaults, are described below.  Driver and  mod-
       ule  specific  configuration  parameters  are described in the relevant
       driver or module manual page.
DESCRIPTION
       Xorg uses a configuration file called xorg.conf for its initial  setup.
       This  configuration  file  is searched for in the following places when
       the server is started as a normal user:
           /etc/X11/<cmdline>
           /usr/etc/X11/<cmdline>
           /etc/X11/$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 <cmdline> 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
       <hostname> is the machine's hostname as reported by gethostname(3).
       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
           /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 <cmdline> 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 <hostname> is the machine's  hostname  as  reported  by
       gethostname(3).
       The  xorg.conf  file  is  composed of a number of sections which may be
       present in any order, or omitted to use default  configuration  values.
       Each section has the form:
           Section  "SectionName"
               SectionEntry
               ...
           EndSection
       The section names are:
           Files          File pathnames
           ServerFlags    Server flags
           Module         Dynamic module loading
           Extensions     Extension enabling
           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  can be absolute directory paths,
              catalogue directories or a font server identifier.  The  formats
              of the later two are explained below:
              Catalogue directories:
                  Catalogue directories can be specified using the prefix cat-
                  alogue: before the directory name. The directory can then be
                  populated  with  symlinks pointing to the real font directo-
                  ries, using the following syntax in the symlink name:
                      <identifier>:[attribute]:pri=<priority>
                  where   <identifier>   is   an   alphanumeric    identifier,
                  [attribute]  is  an  attribute  which  will be passed to the
                  underlying FPE and <priority> is a number used to order  the
                  fontfile FPEs. Examples:
                      75dpi:unscaled:pri=20 -> /usr/share/X11/fonts/75dpi
                      gscript:pri=60 -> /usr/share/fonts/default/ghostscript
                      misc:unscaled:pri=10 -> /usr/share/X11/fonts/misc
              Font server identifiers:
                  Font server identifiers have the form:
                      <trans>/<hostname>:<port-number>
                  where <trans> 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),  <hostname>  is  the  hostname  of  the
                  machine running the font server, and  <port-number>  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 (which can be set inside a cat-
              alogue directory):
                  /usr/lib/X11/fonts/misc/
                  /usr/lib/X11/fonts/TTF/
                  /usr/lib/X11/fonts/OTF/
                  /usr/lib/X11/fonts/Type1/
                  /usr/lib/X11/fonts/100dpi/
                  /usr/lib/X11/fonts/75dpi/
              Font path elements that are found to be invalid are removed from
              the font path when the server starts up.
       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.  The default module path is
                  /usr/lib/xorg/modules
       XkbDir "path"
              sets  the base directory for keyboard layout files.  The -xkbdir
              command line option can be used to override this.   The  default
              directory is
                  /usr/share/X11/xkb
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 "UseSIGIO"  "boolean"
              This controls whether the Xorg server requests that events  from
              input devices be reported via a SIGIO signal handler (also known
              as SIGPOLL on some platforms), or only reported via the standard
              select(3)  loop.   The  default  behaviour is platform specific.
              In general you do not want to use this  option  unless  you  are
              debugging  the  Xorg  server,  or  working around a specific bug
              until it is fixed, and understand 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 Terminate_Server XKB action (usu-
              ally on Ctrl+Alt+Backspace, depending  on  XKB  options).   This
              action is normally used to terminate the Xorg server.  When this
              option is enabled, the action has no effect.  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 "AllowMouseOpenFail"  "boolean"
              This  tells the mousedrv(4) and vmmouse(4) drivers to not report
              failure if the mouse device can't be opened/initialised.  It has
              no  effect on the evdev(4) or other drivers.  The previous func-
              tionality of allowing the server to start up even if  the  mouse
              device  can't  be  opened/initialised  is  now  handled  by  the
              AllowEmptyInput option.  Default: false.
       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 "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: 10 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: 10 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: 10 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 "AIGLX" "boolean"
              enable or disable AIGLX. AIGLX is enabled by default.
       Option "DRI2" "boolean"
              enable or disable DRI2. DRI2 is disabled by default.
       Option "GlxVisuals" "string"
              This option controls how many GLX visuals the GLX  modules  sets
              up.  The default value is typical, which will setup up a typical
              subset of the GLXFBConfigs provided by the driver as  GLX  visu-
              als.   Other  options are minimal, which will set up the minimal
              set allowed by the GLX specification and all  which  will  setup
              GLX visuals for all GLXFBConfigs.
       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.
       Option "AllowEmptyInput" "boolean"
              If enabled, don't add the standard keyboard and  mouse  drivers,
              if  there  are  no input devices in the config file.  Enabled by
              default if AutoAddDevices and AutoEnableDevices is enabled, oth-
              erwise  disabled.   If  AllowEmptyInput is on, devices using the
              kbd, mouse or vmmouse driver are ignored.
       Option "AutoAddDevices" "boolean"
              If this option is disabled, then no devices will be  added  from
              HAL events.  Enabled by default.
       Option "AutoEnableDevices" "boolean"
              If  this option is disabled, then the devices will be added (and
              the DevicePresenceNotify event  sent),  but  not  enabled,  thus
              leaving policy up to the client.  Enabled by default.
       Option "Log" "string"
              This option controls whether the log is flushed and/or synced to
              disk after each message.  Possible values  are  flush  or  sync.
              Unset 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 type of modules normally loaded in this section are
       Xorg server extension 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 DRI extension module can be loaded with the follow-
              ing entry:
                  Load "dri"
       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, extensions, input, internal, and  mul-
       timedia  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 extension modules are available, check the extensions sub-
       directory under:
           /usr/lib/xorg/modules
       The "extmod", "dbe", "dri", "dri2", "glx", and "record" extension  mod-
       ules  are  loaded  automatically,  if they are present, unless disabled
       with "Disable" entries.  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.
EXTENSIONS SECTION
       The Extensions section is used to specify which X11 protocol extensions
       should  be enabled or disabled.  The Extensions section is optional, as
       are all of the entries that may be specified in it.
       Entries in this section are listed as Option statements with  the  name
       of the extension as the first argument, and a boolean value as the sec-
       ond.  The extension name is case-sensitive, and matches the form  shown
       in the output of "Xorg -extension ?".
              Example:  the MIT-SHM extension can be disabled with the follow-
              ing entry:
                  Section "Extensions"
                      Option "MIT-SHM" "Disable"
                  EndSection
INPUTDEVICE SECTION
       The config file may  have  multiple  InputDevice  sections.   Recent  X
       servers  employ  input  hotplugging  to add input devices, with the HAL
       backend being the default backend for X servers since 1.4. It  is  usu-
       ally  not necessary to provide InputDevice sections in the xorg.conf if
       hotplugging is enabled.
       If hotplugging is disabled, there will normally be at  least  two:  one
       for  the  core  (primary)  keyboard  and  one for the core pointer.  If
       either of these two is missing, a default configuration for the missing
       ones will be used. 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 "kbd") driver is used.  The final fallback  is  to  use
       built-in  default  configurations.  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 evdev(4) on Linux sys-
       tems, and kbd(4) and mousedrv(4) on other platforms.
       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"
              Deprecated, use SendCoreEvents instead.
       Option "CoreKeyboard"
              Deprecated, use SendCoreEvents instead.
       Option "AlwaysCore"  "boolean"
              Deprecated, use SendCoreEvents instead.
       Option "SendCoreEvents"  "boolean"
              Both of these options are equivalent, and when enabled cause the
              input  device  to  report core events through the master device.
              They are enabled by default.  Any device configured to send core
              events  will be attached to the virtual core pointer or keyboard
              and control the cursor by default. Devices  with  SendCoreEvents
              disabled  will  be  "floating"  and  only  accessible by clients
              employing the  X  Input  extension.  This  option  controls  the
              startup  behavior only, a device may be reattached or set float-
              ing at runtime.
       Option "SendDragEvents"  "boolean"
              Send core events while dragging. Enabled by default.
       For pointing devices, the following options control how the pointer  is
       accelerated or decelerated with respect to physical device motion. Most
       of these can be adjusted at runtime, see the  xinput(1)  man  page  for
       details.  Only  the  most  important acceleration options are discussed
       here.
       Option "AccelerationProfile"  "integer"
              Select the profile. In layman's terms, the  profile  constitutes
              the "feeling" of the acceleration. More formally, it defines how
              the transfer function (actual acceleration as a function of cur-
              rent  device velocity and acceleration controls) is constructed.
              This is mainly a matter of personal preference.
              0      classic (mostly compatible)
             -1      none (only constant deceleration is applied)
              1      device-dependent
              2      polynomial (polynomial function)
              3      smooth linear (soft knee, then linear)
              4      simple (normal when slow, otherwise accelerated)
              5      power (power function)
              6      linear (more speed, more acceleration)
       Option "ConstantDeceleration"  "real"
              Makes the pointer go deceleration times slower than normal. Most
              useful for high-resolution devices.
       Option "AdaptiveDeceleration"  "real"
              Allows  to  actually  decelerate the pointer when going slow. At
              most, it will be adaptive  deceleration  times  slower.  Enables
              precise pointer placement without sacrificing speed.
       Option "AccelerationScheme"  "string"
              Selects the scheme, which is the underlying algorithm.
              predictable   default algorithm (behaving more predictable)
              lightweight   old acceleration code (as specified in the X protocol spec)
              none          no acceleration or deceleration
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 pciaccess tool scanpci.
       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 "Primary"  "bool"
              This optional entry specifies that the monitor should be treated
              as the primary  monitor.  (RandR  1.2-supporting  drivers  only)
              Option "PreferredMode"  "string" This optional entry specifies a
              mode to be marked as the preferred initial mode of the  monitor.
              (RandR 1.2-supporting drivers 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"  "output"
              This optional entry specifies that the monitor should  be  posi-
              tioned  to  the  left  of  the output (not monitor) of the given
              name.  (RandR 1.2-supporting drivers only)
       Option "RightOf"  "output"
              This optional entry specifies that the monitor should  be  posi-
              tioned  to  the  right  of the output (not monitor) of the given
              name.  (RandR 1.2-supporting drivers only)
       Option "Above"  "output"
              This optional entry specifies that the monitor should  be  posi-
              tioned above the output (not monitor) of the given name.  (RandR
              1.2-supporting drivers only)
       Option "Below"  "output"
              This optional entry specifies that the monitor should  be  posi-
              tioned below the output (not monitor) of the given name.  (RandR
              1.2-supporting 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
              Xorg server.  This option is on by default, but it may be neces-
              sary to turn it off if there are bugs in the driver.  There  are
              many  options to disable specific accelerated operations, 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 "XaaNoOffscreenPixmaps"
              Disables  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 XFree86 (4.2 and earlier)  don't  recognise  the
                  Absolute keyword, so it's safest to just specify the coordi-
                  nates 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 <http://dri.freedesktop.org/>.
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), cvt(1), gtf(1).
       Not all modules or interfaces are available on all platforms.
       Display   drivers:   apm(4),  ati(4),  chips(4),  cirrus(4),  cyrix(4),
       fbdev(4), glide(4), glint(4),  i128(4),  i740(4),  imstt(4),  intel(4),
       mga(4),  neomagic(4),  nv(4), openchrome(4), r128(4), radeon(4), rendi-
       tion(4), savage(4), s3virge(4),  siliconmotion(4),  sis(4),  sisusb(4),
       sunbw2(4),  suncg14(4),  suncg3(4),  suncg6(4),  sunffb(4),  sunleo(4),
       suntcx(4),   tdfx(4),   trident(4),   tseng(4),   vesa(4),   vmware(4),
       voodoo(4), wsfb(4), xgi(4), xgixp(4).
       Input  drivers:  acecad(4),  calcomp(4), citron(4), dmc(4), dynapro(4),
       elographics(4), evdev(4), fpit(4), js_x(4), joystick(4), kbd(4), magic-
       touch(4),   microtouch(4),  mousedrv(4),  mutouch(4),  palmax(4),  pen-
       mount(4),  synaptics(4),  tek4957(4),  ur98(4),  vmmouse(4),   void(4),
       wacom(4).
       Other modules and interfaces: exa(4), fbdevhw(4), v4l(4).
AUTHORS
       This    manual    page   was   largely   rewritten   by   David   Dawes
       <dawes@xfree86.org>.
X Version 11                   xorg-server 1.7.6                  xorg.conf(5)