Here is my example of xorg.conf, how you can setup dual layout for GM945. I'm using laptop screen at 1280x768 and LCD at 1024x768. This config is fully functional of-course

Section "Device"
Identifier "intel"
Driver "i810"
Screen 0
BusID "PCI:0:2:0"
Option "VBERestore" "true"
VideoRam 131072
Option "BackingStore" "true"
Option "BusType" "PCIE"
Option "NoAccel" "false"
Option "DRI" "true"
Option "MonitorLayout" "CRT,LFP"
EndSection

Section "Device"
Identifier "Device1"
Driver "i810"
Screen 1
BusID "PCI:0:2:0"
# Option "VBERestore" "true"
VideoRam 131072
Option "BackingStore" "true"
Option "BusType" "PCIE"
Option "NoAccel" "false"
Option "DRI" "true"
Option "MonitorLayout" "CRT,LFP"
EndSection

Section "Monitor"
Identifier "Generic Monitor"
Option "DPMS"
HorizSync 28-64
VertRefresh 43-60
EndSection

Section "Monitor"
Identifier "AL1914"
Option "DPMS"
HorizSync 31-81
VertRefresh 56-75
EndSection

Section "Screen"
Identifier "Default Screen"
Device "intel"
Monitor "Generic Monitor"
DefaultDepth 24
SubSection "Display"
Viewport 0 0
Depth 16
Modes "1280x768"
EndSubSection
SubSection "Display"
Viewport 0 0
Depth 24
Modes "1280x768"
EndSubSection
EndSection

Section "Screen"
Identifier "Secondary Screen"
Device "Device1"
Monitor "AL1914"
DefaultDepth 24
SubSection "Display"
Depth 16
Modes "1024x768"
EndSubSection
SubSection "Display"
Depth 24
Modes "1024x768"
EndSubSection
EndSection

Section "ServerLayout"
Identifier "Dual-monitor Layout"
Screen 0 "Default Screen"
Screen 1 "Secondary Screen" RightOf "Default Screen"
# Option "Xinerama" "on"
Option "Clone" "On"
InputDevice "Generic Keyboard"
InputDevice "Configured Mouse"
EndSection

Section "DRI"
Mode 0666
EndSection

Position of secondary LCD screen. Keywords for position of the other screen: LeftOf, RightOf, Above, and Below in the section "ServerLayout".

EnJoy :)

Hi, I'm new to linux. I put Ubuntu on my laptop (Sony C290) Everything works great!

The one feature I cannot figure out is the dual monitor thing. I found your posting very helpful, but have some questions.


-Under the monitor section, how do I determine what the Identifier, HorizSync, and VertRefresh values are for my laptop screen as well as my additional monitor?

-Under ServerLayout you have the option set as Clone (with Xinerama commented out) What is Clone?

-And one more question, what happens when I unplug the external LDC?

Any help would be great! I'm trying to learn how to use linux, so some of my questions may be silly and/or obvious.

Here is what I have:
Intel GM945
13.3 laptop screen
17' LCD Dell Monitor
Ubuntu 7.04