[mythtv-users] performance problem on old PC

[Stef Coene]

On Thursday 03 November 2005 00:32, Todd Houle wrote:
> I have been raving about MythTV to a friend of mine who finally
> decided to try it himself.  He had an old PC (1GHz Dell GX150) and 2
> old tuner cards (avermedia and hauppauge win-Tv).  I don't know the
> details of the cards other than they both use the bt878 chips.
>
> We installed KnoppMyth as that is what he heard about elsewhere.
> KnoppMyth detected everything perfectly and ran great.  I added the
> cards in Myth-setup, but we couldn't use it happily.  There was a 1
> second pause, for every second of live tv...  I guess these cards
> don't have hardware MPEG encoders on them and the computer couldn't
> handle the load..  I lowered the quality way down, but still couldn't
> get a smooth playback..
>
> I told him to get a better computer, or a TV card that supports
> hardware encoding.  Was I right?  or was there something else I could
> have done?
I "downgraded" my mythbox from a Athlon 1400 (computer in the living) to a P3, 
700Mhz (computer in the garage).
The P3 can handle my bt878 based card, but I had to switch from rtjpeg to 
mpeg4 (rate of 1800kbit).  When I used rtjpeg, the CPU was not powerfull 
enough so the video was stuttering.  With mpeg4, the myth backend uses 85% 
CPU power.
So it seems that the encoding of mpeg4 needs less cpu than rtjpeg.


Stef