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

[Sergio Monteiro Basto]

On Sun, 2009-01-18 at 11:00 +0800, Zhe Su wrote:
> 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

Hi, yap I am getting same error with x11-driver-video-intel-2.4.2 :

(II) intel(0): Output VGA disconnected
(EE) intel(0): No valid modes.

Seems that is a bug ! 

X won't start, if we have monitor powered off ? 

with vesa drive X starts without any problem  

Best regards,
-- 
Sérgio M. B.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/x-pkcs7-signature
Size: 2192 bytes
Desc: not available
URL: <http://lists.x.org/archives/xorg/attachments/20090118/f28789d1/attachment.bin>