I have a Dell Optiplex GX270 w/ a NVidia GeForceFX 5200 videocard. It has one DVI port on the card and a cable splitter w/ the lables 1 and 2 respectively. I am trying to get a xinerama effect using this card that outputs to to dell flat panel monitors (identical). During the RedHat install the video was displayed identical on both monitors. I checked the XF86config and noticed the driver = "vesa" in the device section for the card. I then downloaded the NVidia driver NVIDIA-Linux-x86-1.0-5336-pkg1.run. I ran it according to the directions. It installed fine. I then changed the XF86config to driver = "nvidia". I then had a single monitor working with the other pitch black. I then edited the XF86config to enable the TwinView option. Here is the basic config:

#**********************************************************
# Monitor section
#**********************************************************

Section "Monitor"
Identifier "My Monitor"
HorizSync 30-121
VertRefresh 48-160
EndSection

#**********************************************************
# Graphics device section
#*********************************************************

Section "Device"
Identifier "NVIDIA"
Driver "nvidia"
VideoRam 131072

EndSection



#**********************************************************
# Screen sections
#**********************************************************

Section "Screen"
Identifier "Screen0"
Device "NVIDIA"
Monitor "My Monitor"
DefaultDepth 24

Option "NvAGP" "1"
Option "TwinView" "true"
Option "SecondMonitorHorizSync" "30.0-121.0"
Option "SecondMonitorVertRefresh" "48.0-160.0"
Option "MetaModes" "1280x1024, 1280x1024; 1280x1024, 1280x1024;"
Option "TwinViewOrientation" "RightOf"
Option "Xinerama" "on"

Subsection "Display"
Depth 8
Modes "1280x1024"
ViewPort 0 0
EndSubsection
Subsection "Display"
Depth 16
Modes "1280x1024"
ViewPort 0 0
EndSubsection
Subsection "Display"
Depth 24
Modes "1280x1024"
ViewPort 0 0
EndSubsection
EndSection


#**********************************************************
# ServerLayout sections.
#**********************************************************

Section "ServerLayout"
Identifier "Layout"

Screen 0 "Screen0" 0 0

InputDevice "Mouse1" "CorePointer"
InputDevice "Keyboard1" "CoreKeyboard"

EndSection


The config does not work properly. One display works, but the other doesn't. The display that is to the right, displays the correct side (the right side) in gnome. The left display is blank. But this is the kicker, I can move the mouse over to the left screen and pull items from it. Example: I pulled the panel bar from the left screen to the right. I then start an app (let's say mozilla) in the desktop panel I can see the window is open, but on the left panel. I then right click on the app on the panel and use move to bring it to the display that works. So basically X is using the Xinerama effect, but I cannot see anything on the left screen. I have looked everywhere for the answer, but I have found nothing. If you have any ideas please reply.