4 monitor setup, configuration problems

saiyanate

We have installed Linux Mint Isadora on a Dell Precision 490 desktop workstation. The video card is an nVidia Quadro NVS 450 and we have hooked up four monitors to it. We want a 2x2 layout with the 'master' monitor being the one on the bottom left. By 'master' I mean that should be the one with the menu bar. But we can't get the xorg.conf to make it work that way.

Suboptimal configuration 1 = All four screens are X-screens, Xinerama enabled, TwinView disabled, and the top left screen is the 'master.'

Suboptimal configuration 2 = The bottom two screens are a pair in Twinview, and the top two are another twinview pair, and xinerama is enabled. The bottom screens are the 'master.'

Suboptimal configuration 3 = same as #2 but in a 1x4 layout (all four monitors in a row).

What we want! = 2x2, Xinerama enabled, no TwinView, bottom left = 'master.' Our xorg.conf for this is pasted below. But when we try to drag the mouse to either of the upper screens, it goes all buggy. Is this a screen configuration issue, or maybe merely a mouse issue? We have tried a number of different layouts and keep coming back to this crazy mouse cursor problem. You can see in the xorg.conf below that I tried commenting out the advanced options for the mouse, but it didn't change a thing.

# PLUG THE MONITORS INTO THE RIGHT SLOTS FOR THIS CONFIG!
# bottom left -> slot 1
# bottom right -> slot 2
# top left -> slot 4
# top right -> slot 3
# system posts on slot 1 always
# slots 1, 4 = PCI 11 = GPU 1
# slots 2, 3 = PCI 10 = GPU 0


#-----keyboard configuration--------------------------
Section "InputDevice"
# generated from default
Identifier "Keyboard0"
Driver "kbd"
EndSection

#-----mouse configuration-----------------------------
Section "InputDevice"
# generated from default
Identifier "Mouse0"
Driver "mouse"
# Option "Protocol" "auto"
Option "Device" "/dev/psaux"
# Option "Emulate3Buttons" "no"
# Option "ZAxisMapping" "4 5"
EndSection

#----- devices here -------------------------

Section "Device"
Identifier "Device0"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "Quadro NVS 450"
BusID "PCI:11:0:0"
Screen 0
EndSection

Section "Device"
Identifier "Device1"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "Quadro NVS 450"
BusID "PCI:10:0:0"
Screen 0
EndSection

Section "Device"
Identifier "Device2"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "Quadro NVS 450"
BusID "PCI:10:0:0"
Screen 1
EndSection

Section "Device"
Identifier "Device3"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "Quadro NVS 450"
BusID "PCI:11:0:0"
Screen 1
EndSection

#----- monitors here -------------------------

Section "Monitor"
# HorizSync source: edid, VertRefresh source: edid
Identifier "Monitor0"
VendorName "Unknown"
ModelName "Samsung SyncMaster"
HorizSync 30.0 - 81.0
VertRefresh 56.0 - 60.0
Option "DPMS"
EndSection

Section "Monitor"
# HorizSync source: edid, VertRefresh source: edid
Identifier "Monitor1"
VendorName "Unknown"
ModelName "Samsung SyncMaster"
HorizSync 30.0 - 81.0
VertRefresh 56.0 - 60.0
Option "DPMS"
EndSection

Section "Monitor"
# HorizSync source: edid, VertRefresh source: edid
Identifier "Monitor2"
VendorName "Unknown"
ModelName "Samsung SyncMaster"
HorizSync 30.0 - 81.0
VertRefresh 56.0 - 60.0
Option "DPMS"
EndSection

Section "Monitor"
# HorizSync source: edid, VertRefresh source: edid
Identifier "Monitor3"
VendorName "Unknown"
ModelName "Samsung SyncMaster"
HorizSync 30.0 - 81.0
VertRefresh 56.0 - 60.0
Option "DPMS"
EndSection

#----- screens here -------------------------

Section "Screen"
Identifier "Screen0"
Device "Device0"
Monitor "Monitor0"
DefaultDepth 24
Option "TwinView" "0"
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 "metamodes" "DFP-0: 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 "metamodes" "DFP-1: nvidia-auto-select +0+0"
SubSection "Display"
Depth 24
EndSubSection
EndSection

Section "Screen"
Identifier "Screen3"
Device "Device3"
Monitor "Monitor3"
DefaultDepth 24
Option "TwinView" "0"
Option "metamodes" "DFP-1: nvidia-auto-select +0+0"
SubSection "Display"
Depth 24
EndSubSection
EndSection

#-----server configuration---------------------

Section "ServerLayout"
Identifier "Layout0"
Screen 0 "Screen0" 0 1080
Screen 1 "Screen1" 1920 1080
Screen 2 "Screen2" 1920 0
Screen 3 "Screen3" 0 0
InputDevice "Keyboard0" "CoreKeyboard"
InputDevice "Mouse0" "CorePointer"
Option "Xinerama" "1"
EndSection

Goineasy9

I don't see what driver your using in the Xorg file (although I'm assuming nvidia blob and not nouveau). If you've installed the nvidia proprietary graphics, I'd see what nvidia-settings proposes as the Xorg.conf. When i used the nvidia blobs, this always worked with my dual monitors.
You can manipulate the layout using nvidia-settings, then take a look at preview (sorry, I think that's what it's called, I've used nouveau since Fedora 13 came out), then compare it, or copy and paste it into the xorg.conf file.
I haven't tried 4 monitors yet, so I can't help further than that. I'm curious as to how you make out.