I have 2 ATI graphics cards and 4 identical Samsung LCDs (2xDVI on each card, no crossfire though the bridge is connected), and I am hoping to configure them in the following manner.
Currently, LCD 1 and 2 work, however 3 and 4 are not recognised. I dual boot Windows 7 and all 4 LCDs work fine in this arrangement, so I think that rules any BIOS misconfiguration out. I am unsure if the fglrx drivers are registering for the second card.
$ fglrxinfo
display: :0.0 screen: 0
OpenGL vendor string: Advanced Micro Devices, Inc.
OpenGL renderer string: AMD Radeon HD 6800 Series
OpenGL version string: 4.2.11903 Compatibility Profile Context
$ lspci | grep VGA
01:00.0 VGA compatible controller: Advanced Micro Devices [AMD] nee ATI Barts XT [Radeon HD 6800 Series]
02:00.0 VGA compatible controller: Advanced Micro Devices [AMD] nee ATI Barts XT [Radeon HD 6800 Series]
$ grep 'Output.*connected' /var/log/Xorg.0.log
[ 5.160] (II) RADEON(0): Output DisplayPort-0 disconnected
[ 5.160] (II) RADEON(0): Output HDMI-0 disconnected
[ 5.160] (II) RADEON(0): Output DVI-0 connected
[ 5.160] (II) RADEON(0): Output DVI-1 connected
$ cat /etc/X11/xorg.conf
# --------------------------------
# CARD1 --------------------------
# --------------------------------
# DEVICES -----------------------
Section "Device"
Identifier "Card1"
Driver "fglrx"
Option "Monitor-DFP6" "Left"
Option "Monitor-DFP7" "Center"
BusID "PCI:1:0:0"
EndSection
# MONITORS -----------------------
Section "Monitor"
Identifier "Left"
Option "VendorName" "Samsung"
Option "ModelName" "BX2450"
Option "DPMS" "true"
Option "PreferredMode" "1920x1080"
Option "TargetRefresh" "60"
#Option "Position" "0 0"
Option "Rotate" "normal"
Option "Disable" "false"
EndSection
Section "Monitor"
Identifier "Center"
Option "VendorName" "Samsung"
Option "ModelName" "BX2450"
Option "DPMS" "true"
Option "PreferredMode" "1920x1080"
Option "TargetRefresh" "60"
#Option "Position" "1920 0"
Option "Rotate" "normal"
Option "Disable" "false"
EndSection
# SCREENS -----------------------
Section "Screen"
Identifier "ScreenLeft"
Device "Card1"
DefaultDepth 24
SubSection "Display"
Viewport 0 0
Virtual 1920 1080
Depth 24
EndSubSection
EndSection
Section "Screen"
Identifier "ScreenCenter"
Device "Card1"
DefaultDepth 24
SubSection "Display"
Viewport 0 0
Virtual 1920 1080
Depth 24
EndSubSection
EndSection
# --------------------------------
# CARD2 --------------------------
# --------------------------------
# DEVICES -----------------------
Section "Device"
Identifier "Card2"
Driver "fglrx"
Option "Monitor-DFP6" "Right"
Option "Monitor-DFP7" "Top"
BusID "PCI:2:0:0"
EndSection
# MONITORS -----------------------
Section "Monitor"
Identifier "Right"
Option "VendorName" "Samsung"
Option "ModelName" "BX2450"
Option "DPMS" "true"
Option "PreferredMode" "1920x1080"
Option "TargetRefresh" "60"
#Option "Position" "3840 0"
Option "Rotate" "normal"
Option "Disable" "false"
EndSection
Section "Monitor"
Identifier "Top"
Option "VendorName" "Samsung"
Option "ModelName" "BX2450"
Option "DPMS" "true"
Option "PreferredMode" "1920x1080"
Option "TargetRefresh" "60"
#Option "Position" "1920 1080"
Option "Rotate" "normal"
Option "Disable" "false"
EndSection
# SCREENS -----------------------
Section "Screen"
Identifier "ScreenRight"
Device "Card2"
DefaultDepth 24
SubSection "Display"
Viewport 0 0
Virtual 1920 1080
Depth 24
EndSubSection
EndSection
Section "Screen"
Identifier "ScreenTop"
Device "Card2"
DefaultDepth 24
SubSection "Display"
Viewport 0 0
Virtual 1920 1080
Depth 24
EndSubSection
EndSection
# --------------------------------
# SERVER -------------------------
# --------------------------------
Section "ServerLayout"
Identifier "myLayout"
Screen "ScreenLeft" 0 0
Screen "ScreenCenter" 1920 0
Screen "ScreenRight" 3840 0
Screen "ScreenTop" 1920 1080
EndSection
Section "ServerFlags"
#Option "Xinerama" "on"
EndSection
