[mythtv-users] Stutter issues with HDTV

[Thomas M. Pluth]

>
> Hi - me again - the HDTV stutter guy. :)
>
> The only way I've been able to get my HDTV 1080i content not to stutter is
> with using XvMC enabled.  Ane I've confirmed the quality of the picture is
> less then "software" enabled de-interlacing support.
>
> So - I'm thinking of buying a new CPU and I'm wondering what speed I
> should get.
>
> I currently have a 2.6G P4 HT 800 FSB.  I've heard from others (Wendy on
> the list) who has had stutter issues with a 3.0 P4 HT.
>
> Do I need to go to 3.2G?  Is this not a CPU issue?  I've had this HDTV
> stutter issue with 0.15.1 and the latest (as of 8/16/04) CVS tree.
>
> Any thoughts before I go my a new processor?  I'm not crazy about the idea
> of doing so - the darn things are expensive.  I thought by getting a
> FX5500 (which would do XvMC) I wouldn't have had to do this.
>
> Thanks,
>
> -John
> --
>

  For my frontend, I'm using a P4 2.8E (800FSB, 1MB Cache) on an Intel
D865GLC motherboard, with PC2700 RAM (512MB) and I'm usually able to
play 1080i without XvMC.   My backend has a P4 2.4 (533FSB, 512KB Cache)
on an Intel D865PERLK motherboard, with PC2700 RAM (1024MB) and I can
only get 1080i content to play with XvMC.  I've compiled the libavcodec
code and all of MythTV with -O3 -march=Pentium4 (which forces use of
SSE, SSE2, and MMX instruction generation from gcc).

  With all that said, I believe Daniel (or someone else) said at one point
that a 2.8Mhz P4 was about the minumum that would play 1080i without
maxing out the CPU (and causing the resultant stuttering).  I'm guessing
your 2.6 is right on the edge.  You will probably see better results
from a 3.0Mhz CPU, which would be a bit cheaper than a 3.2...

  My next move is to enable 4k stacks and SMP to use the Hyperthreading
capabilities of the 2.8E.  I'm also replacing the 2.4 in my backend with
a 3.0E.