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To install Xorg, you just need to run emerge -av xorg-x11. Installing Xorg does take a while though. Before installing Xorg you have to configure two important variables in the /etc/make.conf file.

The first one is VIDEO_CARDS. This is used to set the video drivers that you intend to use and is usually based on the kind and brand of card you have. The most common settings are nvidia for Nvidia cards or fglrx for ATI Radeon cards. Those are the proprietary drivers from Nvidia and ATI respectively. If you would like to use the open source versions, use nv rather than nvidia in the variable, but bear in mind that using this driver means no 3d acceleration at all. The free radeon driver for ATI cards supports full 3D acceleration on older Radeons but doesn't work at all with the newer ones. VIDEO_CARDS may contain more than one driver, in this case list of them should be separated with spaces.

The second variable is INPUT_DEVICES and is used to determine which drivers are to be built for input devices. In most cases setting it to keyboard mouse should work just fine.

Now you should decide which drivers you will use and add necessary settings to the /etc/make.conf file.

Code: Enable mouse and keyboard support
INPUT_DEVICES="keyboard mouse"
Code: Setting the video card
# for nVidia cards

# for ATI Radeon cards

# for Intel GMA cards

Note: You can use multiple values for VIDEO_CARDS. They have to be separated by a whitespace.

More instructions on how to configure Nvidia and ATI cards can be found in Gentoo Linux nVidia Guide and in Gentoo Linux ATI FAQ. If you don't know which drivers you should choose, refer to these guides for more information.

Note: If the suggested settings don't work for you, you should run emerge -pv xorg-server, check all the options available and choose those which apply to your system. The example is for the amd64 architecture and xorg-server-1.2.

Code: Displaying all the driver options available
emerge -pv xorg-server

After setting all the necessary variables you can install the Xorg package.

Code: Installing Xorg
emerge xorg-x11

When the installation is finished, you might need to re-initialize some environment variables before you continue. Just run env-update followed by source /etc/profile and you're all set.


The configuration file of Xorg is called xorg.conf and it resides in /etc/X11/. The Xorg-X11 package provides an example configuration as /etc/X11/xorg.conf.example which you can use to create your own configuration. It is heavily commented, but if you are in need of more documentation regarding the syntax, don't hesitate to read the man page:

Code: Reading the xorg.conf man page
man 5 xorg.conf

A second point of resources on your system is the /usr/X11R6/lib/X11/doc directory with various READMEs for individual graphical chipsets. The following steps will deal with creating the xorg.conf file automatically.

Default: Automatic Generation of xorg.conf

Xorg itself is able to guess most parameters for you. In most cases, you will only have to change some lines to get the resolution you want up and running. If you are interested in more in-depth tweaking, be sure to check the resources at the end of this page. But first, let us generate a (hopefully working) Xorg configuration file.

Code: Generating an xorg.conf file
Xorg -configure

Be sure to read the last lines printed on your screen when Xorg has finished probing your hardware. If it tells you it failed at some point, you're forced to manually write an xorg.conf file. Assuming that it didn't fail, it will have told you that it has written /root/ ready for you to test.

Code: Testing the file
X -config /root/

If all goes well, you should see a simple black and white pattern. Verify if your mouse works correctly and if the resolution is good. If you received errors about "/dev/mouse", try changing your mouse device to /dev/input/mice in the "InputDevice" section of this file. You might not be able to deduce the exact resolution, but you should be able to see if it's too low. You can exit any time by pressing Ctrl-Alt-Backspace.

Copying over xorg.conf

If the generated xorg.conf is working properly, we can copy over the to /etc/X11/xorg.conf now, so we won't have to continuously run X -config. Instead we can use either X or startx.

Alternative: Semi-Automatic Generation of xorg.conf

Xorg provides a tool called xorgcfg which will first attempt to run Xorg -configure and then start the X server for more final tweaking.

Code: Using xorgcfg

In case X crashes or the configuration fails, try:

Code: Using xorgcfg
xorgcfg -textmode

Alternative: Semi-Automatic Generation of xorg.conf

Another tool, also provided by Xorg, called xorgconfig which will ask you for various information regarding your system (graphical adapter, keyboard, ...). It's the text-based version of xorgcfg. Based on your input it will create a xorg.conf file.

Code: Semi-Automatic Generation of xorg.conf


Using startx

Now try startx to start up your X server. startx is a script that executes an X session, that is, it starts the X servers and some graphical applications on top of it. It decides which applications to run using the following logic:

   * If a file named .xinitrc exists in the home directory, it will execute the commands listed there.
   * Otherwise, it will read the value of the XSESSION variable and will execute one of the sessions available in /etc/X11/Sessions/ accordingly (you can set the value of XSESSION in  /etc/rc.conf to make it a default for all the users on the system).
   * If all of the above fail, it will fall back to a simple window manager, usually twm.

You can either do:

Code: Starting X


Code: Starting X

The window manager that starts up is called twm. To get out of it, type in exit in one of the upcoming xterms or simply press Ctrl-D. You can also kill the X session using the Ctrl-Alt-Backspace combination. This will however make X exit disgracefully.

Tweaking xorg.conf

Setting your Resolution

If you feel that the screen resolution is wrong, you will need to check two sections in your configuration. First of all, you have the Screen section which lists the resolutions, if any that your X server will run at. By default, this section might not list any resolutions at all. If this is the case, Xorg will estimate the resolutions based on the information in the second section, Monitor.

What happens is that Xorg checks the settings of HorizSync and VertRefresh in the Monitor section to compute valid resolutions. For now, leave these settings as-is. Only when the changes to the Screen section (which we will describe in a minute) don't work, then you will need to look up the specs for your monitor and fill in the correct values. You can also use a tool that searches for your monitor's specs, such as sys-apps/ddcxinfo-knoppix.

Warning: Do not "just" change the values of these two monitor related variables without consulting the technical specifications of your monitor. Setting incorrect values lead to out-of-sync errors at best and smoked up screens at worst.

Now let us change the resolutions. In the next example from /etc/X11/xorg.conf we add the Modes lines and the DefaultDepth so that our X server starts with 24 bits at 1024x768 by default. Don't mind the given strings -- they are examples and will most likely differ from the settings on your system.

File: /etc/X11/xorg.conf
Section "Screen"
  Identifier  "Default Screen"
  Device    "S3 Inc. ProSavage KN133 [Twister K]"
  Monitor   "Generic Monitor"
  DefaultDepth  24
  # Skipping some text to improve readability
  SubSection "Display"
    Depth   24
    Modes   "1024x768"

Configuring your Keyboard

To setup X to use an international keyboard, search for the InputDevice section that configures the keyboard and add the XkbLayout option to point to the keyboard layout you want. As an example, we show you how to apply for the Belgian layout. Just substitute the country-keycode with yours:

File: /etc/X11/xorg.conf
Section "InputDevice"
  Identifier  "Generic Keyboard"
  Driver    "keyboard"
  Option    "CoreKeyboard"
  Option    "XkbRules"  "xorg"
  Option    "XkbModel"  "pc105"
  Option    "XkbLayout" "be"

Configuring your Mouse

If your mouse isn't working, you will first need to find out if it is detected by the kernel at all. Mice are (device-wise) seen as /dev/input/mouse0 (or /dev/input/mice if you want to use several mice). In some cases /dev/psaux is used. In either case you can check if the devices do represent your mouse by checking the output of those files when you move your mouse. You will usually see some junk on your screen. To end the session press Ctrl-C.

Code: Checking the device files
cat /dev/input/mouse0

Note: Press Ctrl-C to end the execution.

If your mouse isn't detected, verify if all the necessary modules are loaded.

If your mouse is detected, fill in the device in the appropriate InputDevice section. In the next example you'll see we also set two other options: Protocol (which lists the mouse protocol to be used -- most users will use PS/2 or IMPS/2) and ZAxisMapping (which allows for the mousewheel (if applicable) to be used).

File: /etc/X11/xorg.conf
Section "InputDevice"
  Identifier  "TouchPad Mouse"
  Driver    "mouse"
  Option    "CorePointer"
  Option    "Device"    "/dev/input/mouse0"
  Option    "Protocol"    "IMPS/2"
  Option    "ZAxisMapping"    "4 5"

Nvidia cards

If you have a Nvidia card, you would want to run nvidia-settings and tweak a little once you got into X. You need to run nvidia-settings inside of a X session by running startx or you will get a GTK-Warning.

Allow root to start X applications after su'ing

File: /etc/profile
 export XAUTHORITY="${HOME}/.Xauthority" 

One can also use the utility called sux. Just emerge sux and sudo sux -.

this advise is not correct, it results in;

cannot connect to X server


Enable Euro Symbol

Find iso8859-1 in variable definitions of /usr/X11R6/lib/X11/fonts/misc/fonts.alias and replace with iso8859-15.


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Last modified: Sun, 07 Sep 2008 06:47:00 +0000 Hits: 72,023