# Where is the X.org config file? How do I configure X there?

As Ubuntu 10.10 seems to neither detect my graphics card (Intel 82852/855GM) automatically nor use the corresponding Intel driver even after manually installing it, I am looking into manually configuring X (shouldn't I?). Where can I find the configuration files I need to edit?

• Even if you come up with a solution, don't forget to file a bug on Launchpad so that this hardware configuration can be made to work out of the box in future Ubuntu releases. – ændrük Sep 24 '10 at 2:14
• We deliberately don't load the intel driver on your hardware because it is too unstable. See this answer: askubuntu.com/questions/4658/… – RAOF Apr 29 '11 at 8:02

The xorg.conf does not exist by default any more. You CAN create one though.

Boot into recovery mode and select Root Shell. Then run:

X -configure


Then:

cp /root/xorg.conf.new /etc/X11/xorg.conf


Reboot and you can edit the new Xorg.conf.

• This is the correct way. It is just that X now auto-detects the settings, and a xorg.conf is not mandatory. If you know what you want to edit, by all means create one. – NightwishFan Sep 24 '10 at 2:10
• There is absolutely no reason to reboot even once. Just open terminal, write sudo X -configure; sudo cp ... and sudo /etc/init.d/gdm restart (assuming Ubuntu, not KUbuntu). – Olli Mar 19 '11 at 13:31
• @Olli; it doesn't work, you need the X server to be inactive for X -configure to run – Josh G Jun 5 '11 at 0:46
• Josh G: If you are already running X, just say X :1 -configure. You have to open the X server on its own display port; if you already have an X server running, the default port of :0 will fail, so you have to specify display :x (where x is the first available display; in most cases 1). – jeffcook2150 Mar 21 '12 at 18:45
• When running X :1 -configure I have the error : Number of created screens does not match number of detected devices. Configuration failed. ddxSigGiveUp: Closing log Server terminated with error (2). Closing log file. – chmike Feb 4 '13 at 14:37

The configurations files are at /usr/share/X11/xorg.conf.d

They are:

10-evdev.conf

11-evdev-quirks.conf

50-vmmouse.conf

50-wacom.conf

51-synaptics-quirks.conf

Check the current manual.

If you create a xorg.conf file the configurations of this file will prevail.

Usually, you don't need the xorg.conf any more.

If you need to configure some devices anyway, you can do so by placing a file in the /usr/lib/X11/xorg.conf.d/ (Ubuntu 10.04) or /usr/share/X11/xorg.conf.d/ (since Ubuntu 10.10). There are some files in this directory already.

You can find more information on xorg.conf.d (in german, but the configuration files are in english of course). What is important is that the filenames should start with a two-digit number greater than 10.

Another guide - in english - is on x org archive. It's still using /usr/lib but it's good.

• Good point and the rigth way to go. The Arch Wiki also has more on this too (wiki.archlinux.org/index.php/Xorg#Display_Size_and_DPI) though their X server is configured to use /etc/X11/xorg.conf.d/ which makes more sense to me. – Todd Partridge 'Gen2ly' Dec 16 '11 at 20:35
• In Ubuntu, user-added Xorg options should also go into /etc/X11/xorg.conf.d/ files. You'll have to create that directory first, but it works, and is actually mentioned in Ubuntu's /usr/share/X11/xorg.conf.d/* files. – tanius Feb 25 '15 at 3:45

sudo X :1 -configure


worked for me - right from the desktop! It did finally error-out, but not before providing a nice new xorg.conf.new in my Home directory. Thanks cc! All the other suggestions I had tried failed to produce a file.

Oh, by the way,

man xorg.conf


in the terminal will provide a bunch of useful, and up to date, info (a bit terse, perhaps) on editing the xorg.conf file.

• X -config /root/xorg.conf.new – noobninja Aug 20 '15 at 22:35
• It removed my second monitor from my PC. No easy fix for that one, so I guess I have to reinstall ubuntu. Nice one. – Simon Aug 16 '16 at 10:12
• @Simon seriously? Did you try to just undo what you did? (ie, remove the /etc/X11/xorg.conf file?) Read desgua's answer, it explains how the newly created xorg.conf will override all other settings for XOrg. – Adam Plocher Oct 23 '16 at 5:18

Yeah for most free graphics drivers, recent releases of Ubuntu haven't required a xorg.conf file. You can generate one pretty easily though:

sudo Xorg -configure


This works fine for me with Nvidia Optimus (Bumblebee) without any special configuration, just the defaults:

#!/bin/bash
#
# Source: https://bbs.archlinux.org/viewtopic.php?id=140315
#

r=zenity --width 400 --height 250 --title "Display setup" --text "Choose display mode:" --list --column "Modes" "Internal" "External" "Clone" "Extended"

case "\$r" in
Internal)
xrandr --output LVDS1  --auto \
--output VGA1 --off ;;
External)
xrandr --output LVDS1  --off \
--output VGA1 --auto ;;
Clone)
xrandr --output LVDS1  --auto \
--output VGA1 --auto --same-as LVDS1 ;;
Extended)
xrandr --output LVDS1  --auto --primary \
--output VGA1 --auto --left-of LVDS1 ;;
esac


The monitors LVDS1 and VGA1 are defined in ~/.config/monitors.xml. For more information about monitors.xml take a look at http://www.sudo-juice.com/dual-monitor-settings-in-ubuntu/.

Example:

<monitors version="1">
<configuration>
<clone>no</clone>
<output name="LVDS1">
<vendor>AUO</vendor>
<product>0x213c</product>
<serial>0x00000000</serial>
<width>1366</width>
<height>768</height>
<rate>60</rate>
<x>1280</x>
<y>256</y>
<rotation>normal</rotation>
<reflect_x>no</reflect_x>
<reflect_y>no</reflect_y>
<primary>yes</primary>
</output>
<output name="VGA1">
<vendor>GSM</vendor>
<product>0x43ff</product>
<serial>0x00035928</serial>
<width>1280</width>
<height>1024</height>
<rate>60</rate>
<x>0</x>
<y>0</y>
<rotation>normal</rotation>
<reflect_x>no</reflect_x>
<reflect_y>no</reflect_y>
<primary>no</primary>
</output>
<output name="HDMI1">
</output>
<output name="DP1">
</output>
</configuration>
</monitors>


For lost amd users: Please note that amd drivers provide a tool to generate xorg.conf

aticonfig --initial

• aticonfig is proprietary; it does not install with xserver-xorg-video-ati. AMD/ATI users can use xrandr to configure displays. – noobninja Aug 20 '15 at 22:45