[mythtv-users] Video cards, modelines, 720p, HD DLP TVs...

matthew.garman at gmail.com matthew.garman at gmail.com
Tue Jan 30 18:33:54 UTC 2007


My parents and I have nearly identical Samsung DLP TVs (mine is the
HLR5067W, FWIW).  On my parents' MythTV, they're using an Asus M2NPV
motherboard with integrated nvidia geForce 6150 graphics.  This
motherboard comes with a component out "dongle".  To enable the
component out, I had to put the "ConnectedMonitor" "TV" option in
xorg.conf.

What's interesting is this: when using component
out/ConnectedMonitor=TV, the graphics card/driver supports 720
(1280x720) natively---I didn't have to specify a modeline.

Now my setup: I have a Chaintec 7NIF2 motherboard, with integrated
geForce4 MX graphics; only VGA out (might be svideo, but don't want
to use that with my TV ;).  Since I'm using VGA, I have to specify a
modeline.

I've since found that this onboard GPU just won't do XvMC
consistently enough to make this PC useable for HD.  I have an AGP
6200 graphics card laying around.

When I used it, with the VGA out, XvMC worked consistently, but the
screen had *awful* flickering problems (i.e. every second or so, the
whole screen would flicker).

My guess is that there's a problem with my modeline that is causing
the flicker.  FWIW, that AGP card also has DVI out, and I just
bought a DVI->HDMI cable, but I haven't had a chance to test that
yet.

So, several questions:
    - if the GPU/driver can support 1280x720 natively when using
      ConnectedMonitor=TV, why is an explicit modeline required for
      VGA/DVI?
    - does anyone have a definitive answer on whether or not you can
      damage a DLP TV with bad modelines?  (I don't have windows, so
      I can't use the PowerStrip program everyone recommends to find
      my ideal modeline.)
    - anyone happen to have this particular TV and a good modeline?
    - might there be some other problem (other than modeline)
      causing the flickering with the AGP card?
    - in my situation, is there an advantage to use DVI/HDMI over
      VGA?
    - for my parents, is the component out the best route, or should
      I set them up with DVI/VGA as well?

Thanks!
Matt



More information about the mythtv-users mailing list