enabling DDC in the face of broken monitors (was: Re: Intel 915G with Dell 2005FPW TFT no bigger resolution then 1280x1024)

[Philip Prindeville]

Mike A. Harris wrote:

> Xavier Bestel wrote:
>
>> Le jeudi 20 octobre 2005 à 12:52 -0600, Philip Prindeville a écrit :
>>
>>> The EDID reported by this monitor is slightly broken, and I've been
>>> trying to get Dell to fix it, but they have no clue as to what I'm 
>>> talking
>>> about, and their "award winning service" (in India) has no way of
>>> talking to anyone on the factory floor or in the design bureau in
>>> Texas or wherever that might be.
>>
>>
>>
>> FWIW I have plugged it on a pc loaded with Mandriva 2006, and without
>> even touching xorg.conf or anything the desktop booted in 1680x1050. 
>> 100% perfect, I'd like Xorg to be always like that :)
>
>
> The i810 driver changed since 6.8.2, and now defaults to using DDC.
>
> This is not an OS specific change, but an Xorg official driver change.
> Any distribution that ships the newest i810 driver as-is, will
> experience this problem.
>
> Alan Hourihane has mentioned before that this is a bug in the
> display itself, lying about it's EDID data.  The "best" fix
> of course would be for Dell to fix their monitors to report
> the correct EDID data, and magically blast it into the monitor
> firmware without the user knowing about the problem or needing
> to do anything manually.
>
> Unfortunately, it's very unlikely for that to happen.  Judging
> by the number of bug reports I've seen from people with i810
> hardware, this problem is going to affect a large number of users.
>
> I'm wondering if it might be a better idea to revert the changes
> back to the previous behaviour that worked for everyone, even
> though DDC wouldn't be used by default?
>
> IMHO, DDC is just not reliable enough in general to count on.



Say it ain't so, Joe!

I think this would be a big step backwards...  It's like refusing to
turn on the kitchen lights, because you then have to see all the
cockroaches.  ;-)

Yeah, turning on DDC will reveal a lot of bugs, at least initially...
but the product development cycle of monitors is fairly short,
and eventually the bogus monitors will be retired.

And... market forces being what they are, the manufacturers
building monitors that "just work" will get that reputation, and
be rewarded...  and those that don't... Well, they'll learn or perish.

On another front...  Why is the DDC stuff as per-driver as it is?
Why isn't it more generic?  Isn't that the point, after all?

I've also been playing with the idea of having the DDC code
prime the "modeline" list with manufacturer specific modes,
and name them "Native#1", "Native#2", etc. sorted by
highest to lowest resolution.

Thereby, a person could have:

Section "Screen"
       ...
       UseModes "builtin"
       Modes "Native#1" "Native#2" "Native#3"
       ...
EndSection

and the configuration would just work at the highest resolution
the monitor would support (well, and the video adapter).

Comments?

-Philip