[mythtv-users] Re: Very interesting findings

[Neil]

More info for you guys. I did more analysis last night by playing around 
with xorg.conf 

1. Commenting out Option "NoDDC" "True" will allow me watch livetv or watch 
recorded any programs with only DVI cable wire connected. However, EDID 
becomes the master which tells my nvidia card to only use this resolution. 
Unfortunately, EDID is detected incorrectly, that's why we have to specify 
NoDDC 1 or True so that we can attain a max resolution of 1080i. NoDDC is 
the same as IgnoreEDID 1 in xorg.conf 

2. Restoring back Option NoDDC True will prevent me from watching livetv or 
recorded any program and brings the machine to 99% cpu utilization.... 

So who is the culprit here then? Myth? X? Nvidia driver? :D 

Neil writes: 

> Hey guys,  
> 
> I read from a mailing list that using Twinview will degrade HD playback. I 
> am a witness to it and have seen the tearing on some part of the pictures. 
> I have an Nvidia 6600 GT card. This card has a VGA and DVI connectors.  
> 
> Here are my findings:  
> 
> 1. Using twinview Xorg configuration, I am able to see the HD program in 
> my HDTV at 1080i. Quality is totally awesome with some minor bearable 
> tearing. My config for this can be seen at 
> http://restricted.dyndns.org/twinview_xorg.conf  
> 
> 2. I mentioned earlier that using twinview degrades performance. This 
> test, I only had my VGA monitor connected to the VGA port, no DVI 
> connections. So I configured xorg.conf so that it won't be using Twinview. 
> Here is my config for this, 
> http://restricted.dyndns.org/singlehead_xorg.conf and YES, no more 
> tearing.  
> 
> 3. I used the same singlehead xorg.conf for the DVI cable. I disconnected 
> my VGA monitor from the VGA port and connected my DVI cable. I rebooted my 
> machine and bam. I can see the BIOS. So I started my X and am able to see 
> X at 1080i. I started mythfrontend with no issues at all. I can see the 
> menus. However, when I started watching a recorded program, I just get a 
> blank screen and puts my system to 99% cpu utilization.  
> 
> 4. I grabbed the DVI to VGA connector from the Nvidia box. I took out the 
> DVI cable and put the connector. I connected my VGA monitor to this 
> connector and restarted my linux box. BAM again. I was able to see X with 
> the same single head xorg configuration. Mythfronthend runs fine and I am 
> able to watch any recorded programs too.  
> 
> What is this between 3 and 4? Remember, it is working in Twinview. Now, I 
> cannot pinpoint where the problem is coming from.  
> 
> Please help!!!  
> 
> Thanks,  
> 
> Neil
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