[H-GEN] problem with data projector

[Peter Robinson]

McBofh wrote:
> Peter Robinson wrote:
>> I am struggling to make my laptop talk to one of the data projectors 
>> in a lecture room at UQ (3-206). Xorg is defaulting to 800x600.
>> The display on the lecture desk pops up a window saying the optimal 
>> is 1024x768.
>>
>> I am using a Dell Latitude D600  with an ATI Radeon R250 running 
>> Ubuntu Edgy.
>>
>> I did some google searching and found a suggestion - add the 
>> following to the Monitor section of xorg.conf
>>
>> HorizSync  30-61
>> VertRefresh 56-76
>>
>> When I tried that Xorg then defaulted to 640x480  :(
>>
>> I then tried dpkg-reconfigure xserver-xorg with the data projector 
>> connected and it added
>>
>> HorizSync  28-70
>> VertRefresh 43-60
>>
>>
>> Again that gave a resolution of 640x480  (and if I commented those 
>> out it was back to 800x600).
>>
>> It has no trouble with other data projectors around the place (e.g. 
>> 50-2 and 50-3 and our seminar room).
>>
>> Any suggestions on what I should try next?
>
> Either add
>
>         Option  "MonitorLayout" "LVDS,TMDS"
>
> to your xorg.conf's Device section, or use the vesa mode :)
>
> Seriously, I've had no end of problems getting Xorg to work with my
> laptop's ATI card and any external display. With recent builds of
> Xorg (7.1) it's come good again, but I haven't tried a projector.
>
> What I've found - after much annoyance - is that using plain old
> vesa allows everything to sync up just fine.
>
> For reference, I've attached a copy of my working dual-head
> conf file with vesa.
>
> The other thing to ask is, what are the projector models in
> each of those three rooms you mention?
>
>
> James C. McPherson
> -- 
> Solaris kernel software engineer, system admin and troubleshooter
>               http://www.jmcp.homeunix.com/blog
> Find me on LinkedIn @ http://www.linkedin.com/in/jamescmcpherson
>
>

Thanks for the hints James.

The offending data projector has been busy all day - what with O-week - 
but I did find a couple of others that had the same problem.

I first tried adding just

Option  "MonitorLayout" "LVDS,TMDS"

the data projector was still at 800x600 but my laptop screen went haywire :(

However, it prompted me to look more at MonitorLayout and tried

Option  "MonitorLayout" "LVDS,CRT"

That didn't cause a problem with the laptop screen but I was back to 800x600

Looking through your xorg I then added

        Option     "CRT2HSync"    "31-83"      
        Option     "CRT2VRefresh" "50-160"       


That seemed to do the trick :)

I then commented out
Option  "MonitorLayout" "LVDS,CRT"

and it was still fine (but I decided to leave it in at the moment).

(Note: I kept using the ATI driver)

In any case, it looks like this is a workable (if not optimal) solution.

Thanks again,

Peter Robinson