Dual monitor setup on 11.10 without Xinerama AMD/ATI prop. drivers series Radeon 9800

Question

I noticed that using ATI/AMD Radeon 9800 series card and enabling dual monitors with Xinerama, video 3D acceleration doesn't work any more. So I disabled Xinerama and 3D acceleration is back. However, the second monitor, while X display manager (or something) seems to detect it -- it is on and I can move my mouse to it, and right click but there is no desktop GUI on it.

How do I enable another window manager or desktop GUI on the second monitor, or conversely, how do I enable Xinerama with working 3D acceleration?

This is my current xorg.cong file

Section "ServerLayout"
    Identifier     "amdcccle Layout"
    Screen      0  "amdcccle-Screen[1]-0" 0 0
    Screen         "amdcccle-Screen[1]-1" RightOf "amdcccle-Screen[1]-0"
EndSection

Section "Module"
    Load  "glx"
    #Load "fglrx"
EndSection

Section "ServerFlags"
    Option      "Xinerama" "off"
EndSection

Section "Monitor"
    Identifier   "0-DFP3"
    Option      "VendorName" "ATI Proprietary Driver"
    Option      "ModelName" "Generic Autodetecting Monitor"
    Option      "DPMS" "true"
    Option      "PreferredMode" "1680x1050"
    Option      "TargetRefresh" "60"
    Option      "Position" "0 0"
    Option      "Rotate" "normal"
    Option      "Disable" "false"
EndSection

Section "Monitor"
    Identifier   "0-DFP4"
    Option      "VendorName" "ATI Proprietary Driver"
    Option      "ModelName" "Generic Autodetecting Monitor"
    Option      "DPMS" "true"
    Option      "PreferredMode" "1920x1200"
    Option      "TargetRefresh" "60"
    Option      "Position" "0 0"
    Option      "Rotate" "normal"
    Option      "Disable" "false"
EndSection

Section "Device"
    Identifier  "amdcccle-Device[1]-0"
    Driver      "fglrx"
    Option      "Monitor-DFP4" "0-DFP4"
    BusID       "PCI:1:0:0"
EndSection

Section "Device"
    Identifier  "amdcccle-Device[1]-1"
    Driver      "fglrx"
    Option      "Monitor-DFP3" "0-DFP3"
    BusID       "PCI:1:0:0"
    Screen      1
EndSection

Section "Screen"
    Identifier "Default Screen"
    DefaultDepth     24
    SubSection "Display"
    EndSubSection
EndSection

Section "Screen"
    Identifier "amdcccle-Screen[1]-0"
    Device     "amdcccle-Device[1]-0"
    DefaultDepth     24
    SubSection "Display"
        Viewport   0 0
        Depth     24
    EndSubSection
EndSection

Section "Screen"
    Identifier "amdcccle-Screen[1]-1"
    Device     "amdcccle-Device[1]-1"
    DefaultDepth     24
    SubSection "Display"
        Viewport   0 0
        Depth     24
    EndSubSection
EndSection

Answer 1

There is no way for Xinerama to work with 3d acceleration right now, it may possibly work in the future. For the second monitor, the window manager is active, but I'm assuming your using unity, unity can't be forced onto two screens, neither can gnome shell to my understanding. There just to new right now, in the future this will be different. What you can do is switch to a different desktop environment, KDE or gnome 2 or XFCE or even a window manager like open box. From there with in those environments, you can add panels to the second x session.

I know your pain I've been looking for a way to get xinerama fully working with 3d as well but there is none right now.