I have just installed ubuntu but the maximum resolution I can have from within the GUI (System > Preferences > Screen Resolution) is 1280x1040 (see below). My monitor supports up to 1920x1440 and the xorg.conf file recognices this. I'm completely new to Linux and any help is greatly received.

Thanks

# /etc/X11/xorg.conf (xorg 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 /etc/X11/xorg.conf manual page.
# (Type "man /etc/X11/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.
#
# 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 "Files"
FontPath "/usr/share/X11/fonts/misc"
FontPath "/usr/share/X11/fonts/cyrillic"
FontPath "/usr/share/X11/fonts/100dpi/:unscaled"
FontPath "/usr/share/X11/fonts/75dpi/:unscaled"
FontPath "/usr/share/X11/fonts/Type1"
FontPath "/usr/share/X11/fonts/CID"
FontPath "/usr/share/X11/fonts/100dpi"
FontPath "/usr/share/X11/fonts/75dpi"
# paths to defoma fonts
FontPath "/var/lib/defoma/x-ttcidfont-conf.d/dirs/TrueType"
FontPath "/var/lib/defoma/x-ttcidfont-conf.d/dirs/CID"
EndSection

Section "Module"
Load "GLcore"
Load "i2c"
Load "bitmap"
Load "ddc"
Load "dri"
Load "extmod"
Load "freetype"
Load "glx"
Load "int10"
Load "type1"
Load "vbe"
EndSection

Section "InputDevice"
Identifier "Generic Keyboard"
Driver "kbd"
Option "CoreKeyboard"
Option "XkbRules" "xorg"
Option "XkbModel" "pc105"
Option "XkbLayout" "gb"
EndSection

Section "InputDevice"
Identifier "Configured Mouse"
Driver "mouse"
Option "CorePointer"
Option "Device" "/dev/input/mice"
Option "Protocol" "ImPS/2"
Option "Emulate3Buttons" "true"
Option "ZAxisMapping" "4 5"
EndSection

Section "Device"
Identifier "Intel Corporation 82810E DC-133 CGC [Chipset Graphics Controller]"
Driver "i810"
BusID "PCI:0:1:0"
EndSection

Section "Monitor"
Identifier "COMPAQ P1220"
Option "DPMS"
EndSection

Section "Screen"
Identifier "Default Screen"
Device "Intel Corporation 82810E DC-133 CGC [Chipset Graphics Controller]"
Monitor "COMPAQ P1220"
DefaultDepth 24
SubSection "Display"
Depth 1
Modes "1920x1440" "1800x1350" "1600x1200" "1280x1024" "1024x768" "832x624" "800x600" "720x400" "640x480"
EndSubSection
SubSection "Display"
Depth 4
Modes "1920x1440" "1800x1350" "1600x1200" "1280x1024" "1024x768" "832x624" "800x600" "720x400" "640x480"
EndSubSection
SubSection "Display"
Depth 8
Modes "1920x1440" "1800x1350" "1600x1200" "1280x1024" "1024x768" "832x624" "800x600" "720x400" "640x480"
EndSubSection
SubSection "Display"
Depth 15
Modes "1920x1440" "1800x1350" "1600x1200" "1280x1024" "1024x768" "832x624" "800x600" "720x400" "640x480"
EndSubSection
SubSection "Display"
Depth 16
Modes "1920x1440" "1800x1350" "1600x1200" "1280x1024" "1024x768" "832x624" "800x600" "720x400" "640x480"
EndSubSection
SubSection "Display"
Depth 24
Modes "1920x1440" "1800x1350" "1600x1200" "1280x1024" "1024x768" "832x624" "800x600" "720x400" "640x480"
EndSubSection
EndSection

Section "ServerLayout"
Identifier "Default Layout"
Screen "Default Screen"
InputDevice "Generic Keyboard"
InputDevice "Configured Mouse"
EndSection

Section "DRI"
Mode 0666
EndSection

Maybe your monitor can do 1920 but are you sure that your i8210E can manage all that? Older onboard graphics tend to top out at around 1024. My old fx5600 maxed at 1280 60Hz so I ran it at 1024 85Hz.

SFAIK the modes are derived from what you monitor can handle and not from what your VGA can produce.

I suspect you are right as the PC does have onboard graphics and is pretty old. How can I check this though? I am a real novice.

Thanks

One thing you can do to try and eek out the most out of old video cards is to reduce the default depth from 24 to 16. This may allow running a higher resolution.

Note that old i810 graphics can only do 3d hardware acceleration up to 1024x768@16bit. Any higher resolution or any higher bit depth, and 3d acceleration is disallowed (this is a hardware limitation, not just a Linux limitation). I suspect that this limitation will have no effect on you, though. Other than some 3d screensavers, there's not much old i810 3D graphics can handle anyway.

One of the easiest ways is to check with the original manufacturer :-)

X though is pretty good at working out what is the top resolution and will automatically default to that IMX