[CentOS] Does CentOS support dual graphics cards with 2 monitors each?

[Richard Karhuse]

I've got a triple-head set-up running where 1 monitor is off
the internal Intel HD-4000 GPU and 2x monitors are off a GT550-Ti
using the nVidia drivers.  I could not get xrandr support to work
(and attributed that to Intel / nVidia not co-operating).  I found that
using the nVidia xserver setting GUI and hand-editing the xorg.conf
file to be the best solution.  I have similar (but slightly) different
set-ups working under Fedora-17 and CentOS-6.  All 3x screens are
in on large canvass (so screens can be drag from any monitor to any
where on the canvass, e.g., xinerama) across 2x X-servers -- so full
screen either occupies the 1x Dell 24" or the 2x E-Bay 27" "specials".
The key I found is locking things in with the BusID w/PCI designation
settings.

HTH

   -rak-

Here is the xorg.conf -- in case that helps:

# nvidia-settings: X configuration file generated by nvidia-settings
# nvidia-settings:  version 304.37  (mockbuild@)  Tue Aug 14 06:30:17 CEST 2012


Section "ServerLayout"
    Identifier     "Layout0"
    Screen      0  "Screen0" 0 0
    Screen    1  "Screen1" RightOf "Screen0"
    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/input/mice"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"

    # generated from data in "/etc/sysconfig/keyboard"
    Identifier     "Keyboard0"
    Driver         "keyboard"
    Option         "XkbLayout" "us"
    Option         "XkbModel" "pc105"
EndSection

Section "Monitor"

    # HorizSync source: edid, VertRefresh source: edid
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "FRT DIGITAL"
    HorizSync       30.0 - 91.0
    VertRefresh     56.0 - 61.0
    Option         "DPMS"
EndSection

Section "Monitor"
    Identifier    "Monitor1"
    VendorName     "Dell"
    ModelName      "Dell 2405FPW"
    HorizSync       30.0 - 81.0
    VertRefresh     56.0 - 76.0
    Option             "DPMS"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "GeForce GTX 550 Ti"
    BusID       "PCI:1:0:0"
EndSection

Section "Device"
    Identifier "Device1"
    Driver        "intel"
    VendorName "intel"
    BoardName  "intel"
    BusID        "PCI:0:2:0"
    Option        "monitor-HDMI2" "Monitor1"
EndSection

Section "Screen"
    Identifier     "Screen1"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    Option         "Stereo" "0"
    Option         "nvidiaXineramaInfoOrder" "DFP-0"
    Option         "metamodes" "DFP-0: 2560x1440 +0+0, DFP-2:
2560x1440 +2560+0; DFP-0: nvidia-auto-select +0+0, DFP-2:
nvidia-auto-select +2560+0"
#    Option         "metamodes" "DFP-0: 2560x1440 +0+0; DFP-0:
nvidia-auto-select +0+0"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection


Section "Screen"
    Identifier "Screen0"
    Device        "Device1"
    Monitor    "Monitor1"
    DefaultDepth 24
    Option          "metamodes" "HDMI1: 1920x1200 +0+0"
    SubSection    "Display"
           Depth 24
    EndSubSection
EndSection