With xorg intel driver, is it possible to bypass DDC and use a higher resolution?

[Zhe Su]

Hi,
   I just bought a machine with Intel DG45ID mother board. I installed
openSUSE 11.1 and use the on-board graphics card to connect my 37' Full HD
LCD TV via a HDMI cable. However the highest resolution can be used is
1600x1200 instead of the real physical resolution 1920x1080. According to
xorg's log file, the supported resolutions reported by my TV are:

(II) intel(0): EDID vendor "PRI", prod id 5632
(II) intel(0): Using hsync ranges from config file
(II) intel(0): Using vrefresh ranges from config file
(II) intel(0): Printing DDC gathered Modelines:
(II) intel(0): Modeline "800x600"x0.0   40.00  800 840 968 1056  600 601 605
628 +hsync +vsync (37.9 kHz)
(II) intel(0): Modeline "800x600"x0.0   40.00  800 840 968 1056  600 601 605
628 +hsync +vsync (37.9 kHz)
(II) intel(0): Modeline "800x600"x0.0   36.00  800 824 896 1024  600 601 603
625 +hsync +vsync (35.2 kHz)
(II) intel(0): Modeline "640x480"x0.0   31.50  640 656 720 840  480 481 484
500 -hsync -vsync (37.5 kHz)
(II) intel(0): Modeline "640x480"x0.0   31.50  640 664 704 832  480 489 491
520 -hsync -vsync (37.9 kHz)
(II) intel(0): Modeline "640x480"x0.0   30.24  640 704 768 864  480 483 486
525 -hsync -vsync (35.0 kHz)
(II) intel(0): Modeline "640x480"x0.0   25.20  640 656 752 800  480 490 492
525 -hsync -vsync (31.5 kHz)
(II) intel(0): Modeline "720x400"x0.0   28.32  720 738 846 900  400 412 414
449 -hsync +vsync (31.5 kHz)
(II) intel(0): Modeline "1280x1024"x0.0  135.00  1280 1296 1440 1688  1024
1025 1028 1066 +hsync +vsync (80.0 kHz)
(II) intel(0): Modeline "1024x768"x0.0   78.80  1024 1040 1136 1312  768 769
772 800 +hsync +vsync (60.1 kHz)
(II) intel(0): Modeline "1024x768"x0.0   75.00  1024 1048 1184 1328  768 771
777 806 -hsync -vsync (56.5 kHz)
(II) intel(0): Modeline "1024x768"x0.0   65.00  1024 1048 1184 1344  768 771
777 806 -hsync -vsync (48.4 kHz)
(II) intel(0): Modeline "832x624"x0.0   57.28  832 864 928 1152  624 625 628
667 -hsync -vsync (49.7 kHz)
(II) intel(0): Modeline "800x600"x0.0   49.50  800 816 896 1056  600 601 604
625 +hsync +vsync (46.9 kHz)
(II) intel(0): Modeline "800x600"x0.0   50.00  800 856 976 1040  600 637 643
666 +hsync +vsync (48.1 kHz)
(II) intel(0): Modeline "640x480"x75.0   30.72  640 664 728 816  480 481 484
502 -hsync +vsync (37.7 kHz)
(II) intel(0): Modeline "800x600"x72.0   46.87  800 840 920 1040  600 601
604 626 -hsync +vsync (45.1 kHz)
(II) intel(0): Modeline "800x600"x75.0   48.91  800 840 920 1040  600 601
604 627 -hsync +vsync (47.0 kHz)
(II) intel(0): Modeline "1024x768"x70.0   76.16  1024 1080 1192 1360  768
769 772 800 -hsync +vsync (56.0 kHz)
(II) intel(0): Modeline "1280x720"x60.0   74.48  1280 1336 1472 1664  720
721 724 746 -hsync +vsync (44.8 kHz)
(II) intel(0): Modeline "1280x1024"x75.0  138.54  1280 1368 1504 1728  1024
1025 1028 1069 -hsync +vsync (80.2 kHz)
(II) intel(0): Modeline "1600x1200"x60.0  160.96  1600 1704 1880 2160  1200
1201 1204 1242 -hsync +vsync (74.5 kHz)

There is no 1920x1080. It's obviously the reason. Then I searched on google
and found this article: http://en.gentoo-wiki.com/wiki/Intel_GMA. But the
instruction described in this article has no effect. Then I tried to disable
DDC by adding Option "DDC" "off" or "NoDDC", but xorg stopped to work with
following error message:

(**) intel(0): Option "NoDDC"
(II) intel(0): Output VGA disconnected
(II) intel(0): Output HDMI-1 disconnected
(II) intel(0): Output HDMI-2 disconnected
(WW) intel(0): No outputs definitely connected, trying again...
(II) intel(0): Output VGA disconnected
(II) intel(0): Output HDMI-1 disconnected
(II) intel(0): Output HDMI-2 disconnected
(WW) intel(0): Unable to find initial modes
(EE) intel(0): No valid modes.
(II) UnloadModule: "intel"
(II) UnloadModule: "vgahw"
(II) Unloading /usr/lib64/xorg/modules//libvgahw.so
(EE) Screen(s) found, but none have a usable configuration.

I tried my TV with my Macbook Pro via a DVI-HDMI cable, resolution 1920x1080
is supported. So the question is, how can I bypass the information reported
by DDC and let intel driver use specified resolution forcely?

Thanks
James Su
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