[mythtv-users] some things with nvidia cards

[Craig Longman]

ok, on some information i just got from issac, i made some changes to my 
nvidia geforce2 mx setup and have improved my video out a bit, i thought 
i'd pass it along.

many people had suggested to me to use the TwinView option in the driver 
section of the xf86config-4 file.  this worked well, and allowed me to 
have the monitor and the tv going while getting things ready.  but i 
found out that overlays are disabled when in twinview mode.  this showed 
up by running xvinfo, and only seeing an adaptor line like this:

  Adaptor #0: "NV05 Video Blitter"

issac informed me that the Blitter thing doesn't wait for the vsync, 
which neatly explained some image tearing i was seeing (and not happy 
with).  modifying the xf86config-4 to not enable twinview mode, i now 
saw two adaptors:

  Adaptor #0: "NV10 Video Overlay"
  Adaptor #1: "NV05 Video Blitter"

and lo-and-behold, no tearing.

wonderful i thought.  but then i noticed something else.  once i brought 
everything up in 800x600 mode and used nvtv to set the 800x600 huge (the 
only way i can almost fill the width of my pioneer tv) i got the dreaded 
interlacing-looking-crap (where every 4th or so line looks pulled to the 
left), which i believe it was decided it was an xv bug.  i had been 
running in this mode fine before disabling the twinview (and therefore 
enabling the video overlay stuff).  changing everything to 640x480 and 
using nvtv to set 640x480 huge solved that problem nicely, now i have a 
full screen and no tearing.

so, if anyone has tearing problems, try disabling the twinview options. 
 and if anyone is having that xv problem pulling some pixel lines out of 
alignment, try cutting back to 640x480 perhaps and/or stop using nvtv to 
overscan.

anyway, this is a little longer than i wanted, but hopefully the 
explanation and the steps might help someone else if they search this 
off of the archives.

cheers,

    CraigL->Thx();