In IRC, I asked for a bit of help getting my third monitor to become part of my dual monitor display and many posed interested in learning how I accomplished it (if I got it working). Well I got it working, so here is my xorg.conf. I hope it helps.
# nvidia-xconfig: X configuration file generated by nvidia-xconfig
# nvidia-xconfig: version 1.0 (buildmeister@builder26) Fri Dec 15 10:40:27 PST 2006
# /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 "ServerLayout"
Identifier "Default Layout"
# Screen "Second Acer Screen"
# Screen "Default Screen" LeftOf "Second Screen"
# Screen "Polyview Screen"
# Screen "Default Acer Screen"
# Screen "Polyview Screen" RightOf "Default Acer Screen"
Screen 0 "Default Acer Screen" 0 0
Screen 1 "Second Acer Screen" RightOf "Default Acer Screen"
Screen 2 "Polyview Screen" RightOf "Second Acer Screen"
InputDevice "Generic Keyboard"
InputDevice "Configured Mouse"
Option "Xinerama" "on"
Option "Clone" "off"
EndSection
Section "Files"
# paths to defoma fonts
FontPath "/usr/share/X11/fonts/misc"
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/100dpi"
FontPath "/usr/share/X11/fonts/75dpi"
EndSection
Section "Module"
# Load "GLcore"
# Load "dri"
Load "i2c"
Load "bitmap"
Load "ddc"
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" "us"
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 "Monitor"
Identifier "Acer AL1916W Left"
HorizSync 30.0 - 83.0
VertRefresh 55.0 - 75.0
Option "DPMS"
EndSection
Section "Monitor"
Identifier "Acer AL1916W Right"
HorizSync 30.0 - 83.0
VertRefresh 55.0 - 75.0
Option "DPMS"
EndSection
Section "Monitor"
Identifier "Polyview Monitor"
HorizSync 28 - 64
VertRefresh 43 - 60
Option "DPMS"
EndSection
Section "Device"
Identifier "GeForce 7800GT Left"
Driver "nvidia"
BusID "PCI:5:0:0"
Screen 0
EndSection
Section "Device"
Identifier "GeForce 7800GT Right"
Driver "nvidia"
BusID "PCI:5:0:0"
Screen 1
EndSection
Section "Device"
Identifier "Trident Microsystems TGUI 9660/938x/968x (rev 3d)"
Driver "trident"
BusID "PCI:1:6:0"
Screen 0
EndSection
Section "Screen"
Identifier "Default Acer Screen"
Device "GeForce 7800GT Left"
Monitor "Acer AL1916W Left"
DefaultDepth 24
# Option "TwinView"
# Option "ConnectedMonitor" "LCD as 0,LCD as 1"
# Option "TwinViewOrientation" "RightOf"
Option "MetaModes" "1400x900"
Option "RenderAccel" "true"
# Option "SecondMonitorHorizSync" "30-83"
# Option "SecondMonitorVertRefresh" "55-75"
Option "NvAGP" "1"
Option "AllowGLXWithComposite" "true"
SubSection "Display"
Depth 1
Modes "1400x900" "1280x1024" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 4
Modes "1400x900" "1280x1024" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 8
Modes "1400x900" "1280x1024" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 15
Modes "1400x900" "1280x1024" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 16
Modes "1400x900" "1280x1024" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 24
Modes "1400x900" "1280x1024" "1024x768" "800x600" "640x480"
ViewPort 0 0
EndSubSection
EndSection
Section "Screen"
Identifier "Second Acer Screen"
Device "GeForce 7800GT Right"
Monitor "Acer AL1916W Right"
DefaultDepth 24
# Option "TwinView"
# Option "ConnectedMonitor" "LCD as 0,LCD as 1"
# Option "TwinViewOrientation" "RightOf"
Option "MetaModes" "1400x900"
Option "RenderAccel" "true"
# Option "SecondMonitorHorizSync" "30-83"
# Option "SecondMonitorVertRefresh" "55-75"
Option "NvAGP" "1"
Option "AllowGLXWithComposite" "true"
SubSection "Display"
Depth 1
Modes "1400x900" "1280x1024" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 4
Modes "1400x900" "1280x1024" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 8
Modes "1400x900" "1280x1024" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 15
Modes "1400x900" "1280x1024" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 16
Modes "1400x900" "1280x1024" "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 24
Modes "1400x900" "1280x1024" "1024x768" "800x600" "640x480"
ViewPort 0 0
EndSubSection
EndSection
Section "Screen"
Identifier "Polyview Screen"
Device "Trident Microsystems TGUI 9660/938x/968x (rev 3d)"
Monitor "Polyview Monitor"
DefaultDepth 24
SubSection "Display"
Depth 1
Modes "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 4
Modes "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 8
Modes "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 15
Modes "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 16
Modes "1024x768" "800x600" "640x480"
EndSubSection
SubSection "Display"
Depth 24
Modes "800x600" "640x480"
ViewPort 0 0
EndSubSection
EndSection
Section "Extensions"
# Option "Composite" "Enable"
EndSectionIf you have any questions on how it works, I'll be glad to explain it.