FixVideoResolutionHowto

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= FixVideoResolutionHowto =

== Introduction ==
This Howto is intended for those who have installed or upgraded to Hoary, and
their screen resolution is very low. A possible reason for this is that your
hardware (video adapter/monitor) may not have been detected properly. There
are several fixes that I have seen in the forum and in the IRC support channel.
One solution will work for one person and another solution will work for
someone else. I hope to provide several different solutions here, ranked in
decending order from what I have seen to be the most popular and successful
solution to those solutions that have helped only a few. This way, hopefully
it will provide an answer for everyone. Let's start with the most popular fix.

== Run the Autodetect Script Again ==
I'm not sure that this is the solution that works for the most people actually,
but it most certainly is the quickest and easiest one. All we're doing is
running the same script that tried to detect your video hardware when you
initially installed. Sometimes this does help. Run the following command.
{{{
sudo cp /etc/X11/xorg.conf /etc/X11/xorg.conf.custom
sudo sh -c 'md5sum /etc/X11/xorg.conf > /var/lib/xfree86/xorg.conf.md5sum'
sudo dpkg-reconfigure xserver-xorg
}}}
After completion, close any open windows or programs you have running on your
desktop and press {{{CTRL-ALT-Backspace}}} to restart X. You will be asked
to log into your GNOME session again and hopefully everything will be fixed.
If not, try the next solution.

== Undetected Monitor Specs ==
Open the file {{{/etc/X11/xorg.conf}}} in your favourite text editor. I'll assume
you are using {{{nano}}} for an editor as it is fairly straight forward.
{{{
sudo nano /etc/X11/xorg.conf
}}}
Now look for a section in that file called {{{Section "Monitor"}}}. Once you find
this section, look at the lines of text between {{{Section "Monitor"}}}
and {{{EndSection}}}. There should be two lines in there that begin with the
words {{{HorizSync}}} and {{{VertRefresh}}}. If those lines don't appear there
then don't worry. There is a good chance that we've found the problem already!

You will need to gather two bits of information for your monitor now, either
from your User's Manual, the command line, or from online. We need the horizontal sync frequency
(usually measured in kHz) and the vertical refresh rate (usually in Hz).
Finding these values usually just involves searching [http://www.google.com Google]
with the model of your monitor. Both of these values are typically given in a
range such as "30-98 kHZ" or "50-160 Hz". Write those values down, or
otherwise keep them handy. Additionally, if your monitor supports it, you can just run
the following command:
{{{
sudo ddcprobe | grep monitorrange
}}}
The first two values returned are your HorizSync rates, the second pair is your VertRefresh values.

There are two ways to enter your monitor information into the file. One way
is to run the following commands which will regenerate the file and ask you
for the values in the process.
{{{
sudo cp /etc/X11/xorg.conf /etc/X11/xorg.conf.custom
sudo sh -c 'md5sum /etc/X11/xorg.conf > /var/lib/xfree86/xorg.conf.md5sum'
sudo dpkg-reconfigure -plow xserver-xorg
}}}

The second way is to simply add those values to our {{{/etc/X11/xorg.conf}}}
file with a text editor. But first, lets make a backup of that file just in
case an error is made.
{{{
sudo cp /etc/X11/xorg.conf /etc/X11/xorg.conf.backup
}}}

Editing this file so that it works
involves adding two extra lines to the {{{Section "Monitor"}}} section of that
file. For example, mine is shown below.

''NOTE:'' Don't __change__ anything that
is written in the file for now. Just add the two lines. The snippet from my file
is just an example and may not apply to your hardware.
{{{
Section "Monitor"
     Identifier "FLATRON 995F"
     Option "DPMS"
     HorizSync 30-96
     VertRefresh 50-160
EndSection
}}}
Now save the file, close all open applications, and press {{{CTRL-ALT-Backspace}}}
to restart X. Assuming all goes well, you will be prompted to log into your
session again.

== Incorrect DefaultDepth ==
Sometimes the automatic X configuration sets the colour depth to a value
higher than some hardware can properly handle. To see if this is the case for
you, first backup your {{{/etc/X11/xorg.conf}}} file.
{{{
sudo cp /etc/X11/xorg.conf /etc/X11/xorg.conf.backup
}}}
Now open the file in your favourite text editor. I'll assume you'll use {{{nano}}}
for now since it is relatively simple to use, but you can use whatever text
editor you like.
{{{
sudo nano /etc/X11/xorg.conf
}}}
Search for the word {{{DefaultDepth}}} (notice it is one word) in that file.
The default colour depth set by Hoary is typically "24", but as mentioned,
some hardware may not be able to use a value that high. It's pretty safe to
change it to something like "16" just to test whether it solves your video
problems or not. If this change does not solve anything, it is just as simple
to change it back the way it was.

Once the value of {{{DefaultDepth}}} is changed, save the file, close all open
windows on your desktop, and press {{{CTRL-ALT-Backspace}}} to restart X. Assuming
all goes well, you will be prompted to log into GNOME again, hopefully at a
higher resolution.

== The End ==
So far, this is all of the possible solutions I've collected for this problem.
If none of the above corrected your situation, consider posting your question
in the [http://www.ubuntuforums.org Ubuntu Support Forum] or in the #ubuntu
IRC support channel on the {{{irc.freenode.net}}} network.



From nikolaosaidinidis Wed May 4 18:18:27 +0100 2005
From: nikolaos aidinidis
Date: Wed, 04 May 2005 18:18:27 +0100
Subject: video cards
Message-ID: <20050504181827+0100@www.ubuntulinux.org>
#REFRESH 0 http://help.ubuntu.com/community/FixVideoResolutionHowto

FixVideoResolutionHowto (last edited 2008-08-06 16:41:41 by localhost)