On a 1GHZ toshiba tecra 8200 which uses a trident cyberblade XP and a sxga+ LCD
at 1400x1050, the screen is shifted left. The leftmost pixels on the screen
display appear on the right edge of the screen. Note that though this is
occuring for me on Solaris 10, this is documented on linux at
http://bugs.xfree86.org/show_bug.cgi?id=1076 .The solution documented there was
to comment out the lines :

fullSize = (mode->HDisplay == LCD[i].display_x) 
	        && (mode->VDisplay == LCD[i].display_y);

in the trident_dac.c and recompile the driver. I used the Xorg 6.9 tree and it
worked for me.

The following are pertinent entries in the xorg.conf file I used:
Section "Monitor"
        Identifier   "Monitor0"
        VendorName   "Monitor Vendor"
        ModelName    "sxga+"
        HorizSync    28-90
        VertRefresh  40-110
        ModeLine "1400x1050" 107.85  1400 1450 1500 1999  1050 1058 1070 1150
        ModeLine "1280x1024" 108.00  1280 1328 1440 1688  1024 1025 1028 1066
+hsync +vsync
        Option       "dpms"
EndSection
Section "Device"
        Option      "Display1400" "true"
        VideoRAM    16384
        Identifier  "Card0"
        Driver      "trident"
        VendorName  "Trident Microsystems"
        BoardName   "CyberBlade/XP"
        BusID       "PCI:1:0:0"
EndSection
Section "Screen"
        Identifier "Screen0"
        Device     "Card0"
        Monitor    "Monitor0"
        SubSection "Display"
                Depth     16
                Modes     "1400x1050" "1280x1024" "800x600"
        EndSubSection
        SubSection "Display"
                Depth     24
                Modes     "1400x1050" "1280x1024" "800x600"
        EndSubSection
EndSection