A configuração abaixo funcionou redondo com o meu compaq armada e500.
Para substituir vá a consola e digite:
sudo gedit /etc/X11/xorg.conf
Em seguida substítuir o arquivo por:
# xorg.conf (X.Org X Window System server configuration file)
#
# This file was generated by dexconf, the Debian X Configuration tool, using
# values from the debconf database.
#
# Edit this file with caution, and see the xorg.conf manual page.
# (Type "man xorg.conf" at the shell prompt.)
#
# This file is automatically updated on xserver-xorg package upgrades *only*
# if it has not been modified since the last upgrade of the xserver-xorg
# package.
#
# Note that some configuration settings that could be done previously
# in this file, now are automatically configured by the server and settings
# here are ignored.
#
# If you have edited this file but would like it to be automatically updated
# again, run the following command:
# sudo dpkg-reconfigure -phigh xserver-xorg
Section "Screen"
Identifier "Screen 1"
Device "fx5200"
Monitor "meu17"
DefaultDepth 24
Subsection "Display"
Depth 8
Modes "1280x1024" "1024x768" "1152x864" "800x600" "640x480"
ViewPort 0 0
EndSubsection
Subsection "Display"
Depth 16
Modes "1280x1024" "1024x768" "1152x864" "800x600" "640x480"
ViewPort 0 0
EndSubsection
Subsection "Display"
Depth 24
Modes "1280x1024" "1024x768" "1152x864" "800x600" "640x480"
ViewPort 0 0
EndSubsection
EndSection