[mythtv-users] how to determine nvidia-setting vblank options

Nate Crosno nate at crosno.net
Tue Jan 30 21:10:02 UTC 2007

Hi All,

After lots of searching on how to get 1080i going right (I have a list of 
things to try tonight, but that's another story), I am very confused on when 
and why to choose the various nvidia-settings vblank options.  Mostly, I have 
found lots of posts that say "turn this on" or "turn this off", but I cannot 
find any rhyme or reason to it.  Perhaps I am dense (likely), but frequently, 
the instruction are not clear which of the 3 options are being referenced.

I am hoping to understand these settings better so I can choose them under the 
right circumstances rather than flailing in the dark and hoping to eventually 
pick the right ones.

In an effort to be more clear, here are the 3 options I see in the file 


So far, it looks like if component out is used, then all the above should be 
"0", according to http://www.mythtv.org/wiki/index.php/ComponentOut

Steven Adeff (who has been of great help!), recently advised me:
 > Then turn on Xv Vsync in nvidia-settings and use the Standard decoder.

However, we were talking about DVI at the time.  I am confused about which of 
the three this is. Is it the "textures" or "blitter or both?"?

The XvMC wiki page mentions this:
   "Try using the 'nvidia-settings' control panel to disable Video Texture 
Adapter and/or Video Blitter Adapter "Sync to VBlank" checkboxes (on the "X 
Server XVideo Settings" page)"

That must be the second two items I listed from the rc file.

If anyone has more information on what these really do and under what 
circumstances they should be turned on/off, I'd be grateful.

p.s. I did read "How To Ask Questions The Smart Way" -- Hopefully I am doing 
better ;-)  critiques welcome.

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