Wrong DDC information for external monitor with i810

[Christoph Burghardt]

Hi,

i have a Fujitsu P5020D with an Intel 855GM chip. I'm trying to get my
external monitor working.  It gets detected with DDC:

(II) I810(0): Manufacturer: @HA  Model: 101  Serial#: 16843009
(II) I810(0): Year: 2004  Week: 41
(II) I810(0): EDID Version: 1.2
(II) I810(0): Analog Display Input,  Input Voltage Level: 0.700/0.700 V
(II) I810(0): Sync:  Separate
(II) I810(0): Max H-Image Size [cm]: horiz.: 30  vert.: 23
(II) I810(0): Gamma: 2.51
(II) I810(0): DPMS capabilities: StandBy Suspend Off; RGB/Color Display
(II) I810(0): First detailed timing is preferred mode
(II) I810(0): redX: 0.622 redY: 0.307   greenX: 0.271 greenY: 0.555
(II) I810(0): blueX: 0.115 blueY: 0.077   whiteX: 0.282 whiteY: 0.299
(II) I810(0): Supported VESA Video Modes:
(II) I810(0): 720x400 at 70Hz
(II) I810(0): 640x480 at 60Hz
(II) I810(0): 640x480 at 67Hz
(II) I810(0): 640x480 at 72Hz
(II) I810(0): 640x480 at 75Hz
(II) I810(0): 800x600 at 56Hz
(II) I810(0): 800x600 at 60Hz
(II) I810(0): 800x600 at 72Hz
(II) I810(0): 800x600 at 75Hz
(II) I810(0): 832x624 at 75Hz
(II) I810(0): 1024x768 at 60Hz
(II) I810(0): 1024x768 at 70Hz
(II) I810(0): 1024x768 at 75Hz
(II) I810(0): Manufacturer's mask: 0
(II) I810(0): Supported Future Video Modes:
(II) I810(0): #0: hsize: 1024  vsize 768  refresh: 72  vid: 19553
(II) I810(0): #1: hsize: 800  vsize 600  refresh: 70  vid: 19013
(II) I810(0): Supported additional Video Mode:
(II) I810(0): clock: 81.0 MHz   Image Size:  0 x 0 mm
(II) I810(0): h_active: 1280  h_sync: 1328  h_sync_end 1440 h_blank_end 1688 h_border: 0
(II) I810(0): v_active: 768  v_sync: 769  v_sync_end 772 v_blanking: 800 v_border: 0
(II) I810(0): Ranges: V min: 60  V max: 75 Hz, H min: 31  H max: 60 kHz, PixClock max 80 MHz
(II) I810(0): Monitor name: WXGA

Based on this, i've inserted a modeline:

Section "Monitor"
        Identifier      "TV"
        Option          "DPMS"
        Option          "VertRefresh"   "60-75"
        Option          "HorizSync"     "31-60"
        Option          "Modeline" "1280x768 81   1280 1368 1440 1688   768 769 772 800  -hsync -vsync"
EndSection

and i want to get this monitor working with 1280x768

Section "Screen"
        Identifier      "Extern Screen"
        Device          "i810-A"
        Monitor         "TV"
        DefaultDepth    24
        SubSection "Display"
                Viewport        0       0
                Depth           8
                Modes           "1280x768"
        EndSubSection
        SubSection "Display"
                Viewport        0       0
                Depth           15
                Modes           "1280x768"
        EndSubSection
        SubSection "Display"
                Viewport        0       0
                Depth           16
                Modes           "1280x768"
        EndSubSection
        SubSection "Display"
                Viewport        0       0
                Depth           24
                Modes           "1280x768"
        EndSubSection
EndSection


I've already patched with i915resolution the vesa modes but it ends up
with:

*(WW) (1280x768,TV) mode clock 80.14MHz exceeds DDC maximum 80MHz

So xorg ignores my modeline and ignores the extended information from
the monitor. If i set NoDDC, then i only get 640x480. I am out of ideas and would greatly appreciate any
help you could give me.

Thanks,

Christoph Burghardt