[mythtv-users] Cannot get 1400x1050 or 1920x1080 resolution with Sony LCD HDTV

[Jason Surprise]

I just got a Sony 40V2500 LCD and now I'm trying to utilize the PC input 
for my Myth system.  The manual states that I should be able to get 
1400x1050 resolution, but the max I'm able to display is 1280x1024.  The 
desktop thinks it's at 1400x1050 from the KDE screen panel, but when I 
switch from 1280x1024 to 1400x1050, they are identical.  I'm able to 
change to other lower resolutions from the same panel correctly.  I 
notice when in this 'virtual' 1400x1050 mode, the desktop thinks it's 
really in 1400x1050 and cuts off the left of the desktop contents to fit 
in the 1280x1024 resolution.

I have Fedora Core 4 with a Matrox Millenium G450 dual head video 
card.... Here is my xorg.conf:

Section "Monitor"
        Identifier   "Monitor0"
        VendorName   "Monitor Vendor"
        ModelName    "LCD Panel 1920x1200"
        HorizSync    29.0 - 67.0
        VertRefresh  57.0 - 63.0
        Modeline     "1400x1050tv" 101.0 1400 1448 1480 1560 1050 1053 
1057 1080
        Option      "dpms"
EndSection

Section "Device"
        Identifier  "Videocard0"
        Driver      "mga"
        VendorName  "Videocard vendor"
        BoardName   "Matrox Millennium G450"
EndSection

Section "Screen"
        Identifier "Screen0"
        Device     "Videocard0"
        Monitor    "Monitor0"
        DefaultDepth     16
        SubSection "Display"
                Viewport   0 0
                Depth     16
                Modes    "1400x1050tv" "1280x960" "1280x800" "1280x1024" 
"1152x864" "1024x768" "800x600" "640x480"
        EndSubSection
        SubSection "Display"
                Viewport   0 0
                Depth     24
                Modes    "1400x1050tv" "1280x960" "1280x800" "1280x1024" 
"1152x864" "1024x768" "800x600" "640x480"
        EndSubSection
EndSection

Here are relevant portions of the Xorg.0.log:

(II) MGA(0): Supported additional Video Mode:
(II) MGA(0): clock: 101.0 MHz   Image Size:  880 x 490 mm
(II) MGA(0): h_active: 1400  h_sync: 1448  h_sync_end 1480 h_blank_end 
1560 h_border: 0
(II) MGA(0): v_active: 1050  v_sync: 1053  v_sync_end 1057 v_blanking: 
1080 v_border: 0
...
(--) MGA(0): Has SDRAM
(--) MGA(0): Virtual size is 1400x1050 (pitch 1408)
(**) MGA(0): *Mode "1400x1050tv": 101.0 MHz, 64.7 kHz, 59.9 Hz
(II) MGA(0): Modeline "1400x1050tv"  101.00  1400 1448 1480 1560  1050 
1053 1057 1080


Also, I've read threads from people having success using native 
1920x1080 through the PC input even though it's not officially supported 
in the manual.  I would really like to try this out and see if I can run 
Myth at 1920x1080.  The G450 manual says that is can do 1920x1200.  Is 
there any way to trick the card to thinking it's in 1920x1200 mode, but 
really output 1920x1080?

Thanks
Jason