I have a Debian 7.0 system which I'm trying to set up with 3 monitors. I'm using a Quadro NVS 420 card with the latest NVidia drivers. I configured it using Xinerama and the nvidia-settings utility, and the three desktops appear just fine, but on the main one all of the GNOME UI elements are duplicated, e.g. the menu items at the top black bar all appear twice. Each menu of the duplicates is fully functional so it's not just a display issue.
I don't even know where to look for what would cause this. Here is my xorg.conf:
# nvidia-settings: X configuration file generated by nvidia-settings
# nvidia-settings: version 295.59 (buildmeister@swio-display-x86-rhel47-03.nvidia.com) Wed Jun 6 22:23:02 PDT 2012
Section "ServerLayout"
Identifier "Layout0"
Screen 0 "Screen0" 0 0
Screen 1 "Screen1" 3360 0
Screen 2 "Screen2" 1680 0
InputDevice "Keyboard0" "CoreKeyboard"
InputDevice "Mouse0" "CorePointer"
Option "Xinerama" "1"
EndSection
Section "Files"
EndSection
Section "InputDevice"
# generated from default
Identifier "Mouse0"
Driver "mouse"
Option "Protocol" "auto"
Option "Device" "/dev/psaux"
Option "Emulate3Buttons" "no"
Option "ZAxisMapping" "4 5"
EndSection
Section "InputDevice"
# generated from default
Identifier "Keyboard0"
Driver "kbd"
EndSection
Section "Monitor"
# HorizSync source: edid, VertRefresh source: edid
Identifier "Monitor0"
VendorName "Unknown"
ModelName "DELL 2009W"
HorizSync 30.0 - 83.0
VertRefresh 56.0 - 75.0
Option "DPMS"
EndSection
Section "Monitor"
# HorizSync source: edid, VertRefresh source: edid
Identifier "Monitor1"
VendorName "Unknown"
ModelName "DELL 2009W"
HorizSync 30.0 - 83.0
VertRefresh 56.0 - 75.0
Option "DPMS"
EndSection
Section "Monitor"
# HorizSync source: edid, VertRefresh source: edid
Identifier "Monitor2"
VendorName "Unknown"
ModelName "DELL 2009W"
HorizSync 30.0 - 83.0
VertRefresh 56.0 - 75.0
Option "DPMS"
EndSection
Section "Device"
Identifier "Device0"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "Quadro NVS 420"
BusID "PCI:3:0:0"
Screen 0
EndSection
Section "Device"
Identifier "Device1"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "Quadro NVS 420"
BusID "PCI:4:0:0"
EndSection
Section "Device"
Identifier "Device2"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "Quadro NVS 420"
BusID "PCI:3:0:0"
Screen 1
EndSection
Section "Screen"
Identifier "Screen0"
Device "Device0"
Monitor "Monitor0"
DefaultDepth 24
Option "TwinView" "0"
Option "TwinViewXineramaInfoOrder" "DFP-1"
Option "metamodes" "DFP-0: nvidia-auto-select +0+0"
SubSection "Display"
Depth 24
EndSubSection
EndSection
Section "Screen"
Identifier "Screen1"
Device "Device1"
Monitor "Monitor1"
DefaultDepth 24
Option "TwinView" "0"
Option "TwinViewXineramaInfoOrder" "DFP-0"
Option "metamodes" "nvidia-auto-select +0+0"
SubSection "Display"
Depth 24
EndSubSection
EndSection
Section "Screen"
Identifier "Screen2"
Device "Device2"
Monitor "Monitor2"
DefaultDepth 24
Option "TwinView" "0"
Option "TwinViewXineramaInfoOrder" "DFP-1"
Option "metamodes" "DFP-1: nvidia-auto-select +0+0"
SubSection "Display"
Depth 24
EndSubSection
EndSection
Section "Extensions"
Option "Composite" "Disable"
EndSection