[mythtv-users] Strange resolution problem

Mon Jul 6 14:07:37 UTC 2015

Hoi Stephen,

Monday, July 6, 2015, 3:46:44 PM, you wrote:

> On Mon, 06 Jul 2015 11:32:13 +0100, you wrote:

>>On 04/07/2015 08:29, Alec Leamas wrote:
>>> On 04/07/15 08:57, Andréas Kühne wrote:
>>>> What I would do is check the EDID properties of the projector, also
>>>> perhaps change the settings in mythbuntu to not care about the EDID
>>>> values. I don't know how to do that however.
>>>
>>> I did this long time ago for a monitor with a long cable, long enough 
>>> to make EDID fail. The solution was to add a modeline to xorg.conf, in 
>>> my case it looks like this (mind the email linebreaks). It still works.
>>>
>>> Section "Monitor"
>>>     Identifier     "Monitor0"
>>>     VendorName     "IBM"
>>>     ModelName      "ThinkVision L190"
>>>     HorizSync       15.0 - 70.0
>>>     VertRefresh     58.0 - 64.0
>>>     ModeLine     "1280x1024_60.00" 108.9 1280 1360 1496 1712 1024 1025 
>>> 1028 1060 -hsync +vsync
>>>     Option         "DPMS"
>>> EndSection
>>>
>>>
>>> Part of this lesson was that a cable can work in the video sense while 
>>> still not having bandwidth enough for EDID.
>>>
>>>> Of course, I could be totally wrong, but it was the only thing I 
>>>> could think of.
>>>
>>>
>>> OTOH, perhaps you're right :)
>>OK, so here's an update.
>>
>>I created an empty xorg.conf file and entered the following:
>>
>>Section "Monitor"
>>Identifier "Monitor0"
>>VendorName "BenQ"
>>ModelName "W1300"
>># 1920x1080 @ 60.00 Hz (GTF) hsync: 67.08 kHz; pclk: 172.80 MHz
>>Modeline "1920x1080_60.00" 172.80 1920 2040 2248 2576 1080 1081 1084 
>>1118 -HSync +Vsync
>># 1920x1080 @ 50.00 Hz (GTF) hsync: 55.60 kHz; pclk: 141.45 MHz
>>Modeline "1920x1080_50.00" 141.45 1920 2032 2232 2544 1080 1081 1084 
>>1112 -HSync +Vsync
>>EndSection
>>
>>And it has improved things a lot, but not completely. Maybe 75% better.
>>
>>The first thing I did was test a particularly bad scene from a program I 
>>watched a few nights ago. That would now play without any problems. So, 
>>I decided to watch a full film last night. It was pretty good 
>>throughout, but at about 3 points throughout the film, it had two or 
>>three of these 'black and searching' screens, then after a couple of 
>>seconds it pops back up having found the resolution again (switching 
>>between 1920x1080 and 1919x1080).
>>
>>Also, this morning, I plugged my office windows PC into the projector. 
>>That seemed to play everything fine and 1920x1020. The 'searching' thing 
>>didn't happen once.
>>
>>Any more ideas to fix that final 25%?
>>
>>I'm wondering if theres a way to remove any ability to go to the 
>>1919x1080 resolution? Although maybe that would leave me with a 
>>completely blank screen?
>>
>>One thing I did notice is that I was expecting the monitor name in the 
>>GUI display settings to have changed to BenQ or W1300. It haddn't, it 
>>was still on whatever the default of automated setting thought that the 
>>monitor was. Maybe this means that the monitor identifier value is wrong?
>>
>>Thanks,
>>Damian

> Check your xorg.0.log file.  I think you will find that there are
> other automatically generated modelines that it can still switch to.
> You probably need to find all the options to set that prevent X from
> using anything except your manually created modelines, because by
> default it will use the EDID ones as well, and often a default set of
> VESA ones too.  It just uses yours first, but has the others available
> at lower priority.  I do not remember what the options all are - it is
> too long ago since I last had to fiddle with modelines.  I think one
> of them is to prevent X from reading the EDID data at all, so it can
> not use that.

> The name you need to use to identify the projector as the monitor
> should also show up in xorg.0.log.  This is what I get in the log from
> the Nvidia drivers:

> [544296.381] (--) NVIDIA(0): Valid display device(s) on GeForce GT 220
> at PCI:1:0:0
> [544296.381] (--) NVIDIA(0):     CRT-0
> [544296.381] (--) NVIDIA(0):     CRT-1
> [544296.381] (--) NVIDIA(0):     SONY TV (DFP-0) (connected)
> [544296.381] (--) NVIDIA(0):     DFP-1

> The only connected device is my TV, so the ID value is "Sony TV" and
> it is connected on the DFP-0 port (the first DVI port on my GT 220
> card).  So here is my working xorg.conf:

> Section "Monitor"
>         Identifier "Sony TV"
>         Option "DPMS"   "true"
> EndSection

> Section "Device"
>         Identifier "Nvidia GT220"
>         Driver "nvidia"
>         Option "DPI"    "100x100"
>         Option "NoLogo" "1"
> EndSection

> Section "Screen"
>         Identifier "Default Screen"
>         Monitor         "Sony TV"
>         Device          "Nvidia GT220"
>         DefaultDepth    24
>         Option          "FlatPanelProperties"   "Scaling = Native"
> EndSection

> Section "ServerFlags"
>         Option "BlankTime"              "0"
>         Option "StandbyTime"    "0"
>         Option "SuspendTime"    "0"
>         Option "OffTime"                "0"
> EndSection

> Section "Extensions"
>         Option "Composite"      "Disable"
> EndSection

> I needed to have an xorg.conf in order to set the DMPS timeouts to 0
> (disabled), and for the DPI 100x100 and Scaling=Native settings, which
> prevented some software from using far too small a font size.  Since I
> had to put those options in, the Nvidia drivers and X have been
> upgraded a number of times, so I am not sure if they are still needed
> any more, although the DPMS timeouts probably are.
> _______________________________________________

For disabling metamodes in nvidia look at:
Option "IncludeImplicitMetaModes" "boolean"
in the readme coming with the driver.

Tot mails,
  Hika                            mailto:hikavdh at gmail.com

"Zonder hoop kun je niet leven
Zonder leven is er geen hoop
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