Upgrade from Ubuntu 6.06 to 6.10 beta breaks X

Binary package hint: xserver-xorg-video-trident

This system is a Toshiba Tecra M1 with a Trident Microsystems CyberBlade XP4m32 according to /var/log/Xorg.0.log.

When I upgraded this morning, X would start but just left garbage on the screen. The keyboard worked, so I could log in, but could not see what I was doing.

By booting in recovery mode, I was able to cobble together a working xorg.conf using Xorg -configure, then commenting out the line:
# Load "dri"

And changing the line referring to /dev/mouse to:
        Option "Device" "/dev/input/mice"

Before the upgrade, I was using the following line in xorg.conf, but have had to leave it commented out:
        #Option "ShadowFB" "true"

I played around with xorg.conf for a while, but haven't found a satisfactory solution to get to parity with what I had using 6.06.

My current xorg.conf, as follows, leaves something to be desired: Whenever I move a window, the content gets garbled. I have to minimize and restore the window to get a readable version again.

Section "ServerLayout"
        Identifier "X.org Configured"
        Screen 0 "Screen0" 0 0
        InputDevice "Mouse0" "CorePointer"
        InputDevice "Keyboard0" "CoreKeyboard"
EndSection

Section "Files"
        RgbPath "/usr/share/X11/rgb"
        ModulePath "/usr/lib/xorg/modules"
        FontPath "/usr/share/fonts/X11/misc/"
        FontPath "/usr/share/fonts/X11/TTF/"
        FontPath "/usr/share/fonts/X11/OTF"
        FontPath "/usr/share/fonts/X11/Type1/"
        FontPath "/usr/share/fonts/X11/CID/"
        FontPath "/usr/share/fonts/X11/100dpi/"
        FontPath "/usr/share/fonts/X11/75dpi/"
EndSection

Section "Module"
        Load "dbe"
# Load "dri"
        Load "extmod"
        Load "glx"
        Load "record"
        Load "xtrap"
        Load "freetype"
        Load "type1"
EndSection

Section "InputDevice"
        Identifier "Keyboard0"
        Driver "kbd"
EndSection

Section "InputDevice"
        Identifier "Mouse0"
        Driver "mouse"
        Option "Protocol" "auto"
        Option "Device" "/dev/input/mice"
        Option "ZAxisMapping" "4 5 6 7"
EndSection

Section "Monitor"
        #DisplaySize 290 220 # mm
        Identifier "Monitor0"
        VendorName "TOS"
        ModelName "rnal Panel"
        Option "DPMS"
EndSection

Section "Device"
        ### Available Driver options are:-
        ### Values: <i>: integer, <f>: float, <bool>: "True"/"False",
        ### <string>: "String", <freq>: "<f> Hz/kHz/MHz"
        ### [arg]: arg optional
        #Option "AccelMethod" # [<str>]
        #Option "SWcursor" # [<bool>]
        #Option "PciRetry" # [<bool>]
        #Option "NoAccel" # [<bool>]
        #Option "SetMClk" # <freq>
        #Option "MUXThreshold" # <i>
        #Option "ShadowFB" # [<bool>]
        #Option "Rotate" # [<str>]
        #Option "VideoKey" # <i>
        #Option "NoMMIO" # [<bool>]
        #Option "NoPciBurst" # [<bool>]
        #Option "MMIOonly" # [<bool>]
        #Option "CyberShadow" # [<bool>]
        #Option "CyberStretch" # [<bool>]
        #Option "XvHsync" # <i>
        #Option "XvVsync" # <i>
        #Option "XvBskew" # <i>
        #Option "XvRskew" # <i>
        #Option "FpDelay" # <i>
        #Option "Display1400" # [<bool>]
        #Option "Display" # [<str>]
        #Option "GammaBrightness" # [<str>]
        #Option "TVChipset" # [<str>]
        #Option "TVSignal" # <i>
        Identifier "Card0"
        Driver "trident"
        VendorName "Trident Microsystems"
        BoardName "CyberBlade XP4m32"
        BusID "PCI:1:0:0"
        Option "CyberShadow" "True"
        #Option "ShadowFB" "true"
        Option "NoAccel" "false"
EndSection

Section "Screen"
        Identifier "Screen0"
        Device "Card0"
        Monitor "Monitor0"
        SubSection "Display"
                Viewport 0 0
                Depth 1
        EndSubSection
        SubSection "Display"
                Viewport 0 0
                Depth 4
        EndSubSection
        SubSection "Display"
                Viewport 0 0
                Depth 8
        EndSubSection
        SubSection "Display"
                Viewport 0 0
                Depth 15
        EndSubSection
        SubSection "Display"
                Viewport 0 0
                Depth 16
        EndSubSection
        SubSection "Display"
                Viewport 0 0
                Depth 24
        EndSubSection
EndSection