[mythtv-users] Still no X window on my LCD TV.

[Jakob Fix]

My diskless mythbox was running fine when used with a standard CRT
computer monitor.  But now that I want to connect it to my newly
acquired LCD TV, X window starts, but the TV set says "Not supported
mode" and displays nothing (usually I see xdm's login screen).


I'm sorry if what I'm asking sounds stupid, but I just can't get my
head around these problems.  And believe me, I searched the web.


First, the equipment:
====================
Graphics card: integrated ATI 9100 Pro IGP (on a Asus Pundit R350) with DVI out
    Xorg.0.log says:
    (--) Chipset ATI Radeon 9100 PRO IGP 7834 found

    connected to the TV via a DVI-HDMI cable

TV: Samsung LE32R51B, with HDMI input, and 1360x768 resolution
    it has also VGA input (called "PC" by the handbook) which I'm _not_ using

    The manual gives this information about the TV

       Horizontal frequency: 30 - 61 kHz
       Vertical frequency  : 60 - 75 Hz

    Then, later on, under the heading "Display Mode (PC)" (i.e. VGA):

    "The below table shows all the display modes that are supported:

    Mode   Resolution  Horiz Freq Vert Freq Pix Clck (MHz) Sync Polarity
                          (kHz)       (Hz)     (MHz)         (H/V)
    -----------------------------------------------------------------------
    ...
    VESA:   640 x 480     37.861    72.809     31.500         -/-
           ...
           1024 x 768     60.023    75.029     78.750         +/+
           1360 x 768     47.712    60.015     85.800         +/+

    Note: The interlace mode is not supported.
    Note: The set might operate abnormally if a non-standard video
format is used.
    Note: DVI dose does not support PC function."

So, is this information relevant at all for my case where I connect
the computer via DVI to the TV's HDMI input?


My understanding is this:

The graphics card supports a certain number of resolutions.  The TV
supports another set of resolutions.  The overlap of these two sets is
the one I can use for display.


What does it mean when I see the following in the Xorg.0.log?

(II) RADEON(0): PLL parameters: rf=1432 rd=6 min=20000 max=35000; xclk=16670
(WW) RADEON(0): Failed to detect secondary monitor, MergedFB/Clone mode disabled
(==) RADEON(0): Using gamma correction (1.0, 1.0, 1.0)
(II) RADEON(0): Validating modes on Primary head ---------
(II) RADEON(0): DFP table revision: 2
(II) RADEON(0): Panel infos found from DDC detailed: 1280x720
(II) RADEON(0): Valid Mode from Detailed timing table: 1280x720
(II) RADEON(0): Valid Mode from Detailed timing table: 1280x720
(II) RADEON(0): Valid Mode from established timing table: 640x480

Does this mean the TV supports these resolutions, or is this what the
graphics card supports?

(II) RADEON(0): Total of 3 mode(s) found.
(II) RADEON(0): Total number of valid DDC mode(s) found: 3
(WW) RADEON(0): Mode 1360x768 is out of range.

Is this the graphics card complaining?  Is this a case where the
Option "IgnoreEDID" should be added to the xorg.conf file?

(WW) RADEON(0): Valid modes must be between 320x200-1280x720
(WW) RADEON(0): Mode 1360x765 is out of range.
(WW) RADEON(0): Valid modes must be between 320x200-1280x720
(II) RADEON(0): Valid mode using on-chip RMX: 1280x720
(WW) RADEON(0): Mode 1024x768 is out of range.
(WW) RADEON(0): Valid modes must be between 320x200-1280x720
(II) RADEON(0): Valid mode using on-chip RMX: 800x600
(II) RADEON(0): Valid mode using on-chip RMX: 640x480
(II) RADEON(0): Total number of valid FP mode(s) found: 3
(--) RADEON(0): Virtual size is 1280x720 (pitch 1280)
(**) RADEON(0): *Mode "1280x720": 74.2 MHz (scaled from 0.0 MHz), 45.0
kHz, 60.0 Hz
(II) RADEON(0): Modeline "1280x720"   74.25  1280 1390 1430 1650  720
725 730 750
(**) RADEON(0): *Mode "800x600": 74.2 MHz (scaled from 0.0 MHz), 45.0
kHz, 60.0 Hz
[...]

Great, I see Modelines in the log output!  Let's use them.  I've put
them in my xorg.conf file (see below), but still no joy (i.e. the TV
says "Not supported mode" and nothing is displayed):

### is the following enough in the Monitor section, or do I need something else?

Section "Monitor"
    Identifier  "Samsung LCD TV"

    ### these three from the log output of Xorg.0.log
    Modeline "1280x720" 74.25  1280 1390 1430 1650  720 725 730 750
    Modeline "800x600"  74.25  800 1390 1430 1650  600 725 730 750
    Modeline "640x480"  74.25  640 1390 1430 1650  480 725 730 750

    ### this one from the myth modeline database, thanks Steven.
    Modeline "1360x768" 85.500 1360 1424 1536 1792 768 771 777 795 +Hsync +Vsync

    ### do I need this information, or is it already contained in the modelines?
    HorizSync   30-61
    VertRefresh 60
EndSection

Section "Device"
    Identifier  "ATI Radeon 9100 Pro IGP"
    Driver      "radeon"
    VideoRam    65536
EndSection

### does this look reasonable?

Section "Screen"
    Identifier   "Screen 1"
    Device       "ATI Radeon 9100 Pro IGP"
    Monitor      "Samsung LCD TV"
    DefaultDepth 24

    Subsection   "Display"
        Depth    8
        Modes    "1360x768" "1360x765" "1280x720" "1024x768" "800x600" "640x480"
        ViewPort 0 0
    EndSubsection
    Subsection "Display"
        Depth    16
        Modes    "1360x768" "1360x765" "1280x720" "1024x768" "800x600" "640x480"
        ViewPort 0 0
    EndSubsection
    Subsection "Display"
        Depth    24
        Modes    "1360x768" "1360x765" "1280x720" "1024x768" "800x600" "640x480"
        ViewPort 0 0
    EndSubsection
EndSection


Really, I'm currently at my wits' end and really appreciate your help.



-- 
cheers,
Jakob.