MythTV not smooth while viewing TV

Hi all,

I've been running a mythtv htpc using a Hauppauge 350 for the last year
and been quite happy with it. One issue I've always had was that when I
watched TV through MythTV, the playback and audio were jerky. Though
when I watch a previously recorded program (usually with Kaffeine), the
playback is totally smooth.

I'm guessing this is due to a limitation/bottleneck with my system.
* 3.6GHz P4 CPU
* 128Mb Radeon 9250 PCI video card
* 512Mb ECC DDR2-400
* 2x300Gb SATA-150
* 1280x768 @ 60hz output to my LCD TV
* E7221 chipset
* Mandriva 2007 OS
While I have plenty of CPU overhead, I'm guessing the bottleneck is the
old chipset and having to run my video through a PCI slot. (I don't
have a choice. Dell mutilated the PCI-E slot so you can't put a card in
it. The on-board graphics can't handle the resolution.) The specs on
the video card are 6.4Gb/s, comparable to low-end PCI-E cards (eg
nvidia 7300GS). So, I'd bet my problem is with the chipset.

I recently added a HD5000 card to receive (H)DTV broadcasts and it has
the same live-playing jerkiness.

Before I drop cash to upgrade the system, I'm looking to see whether
there are any suggestions to improve watching the TV through MythTV.

I've been looking at upgrading to:
* E6700 Core 2 (I already have one!)
* ASUS P5LD2 2.0
* 1Gb DDR2-533
* Radeon x550
The board and video card are older and lower-end, but I believe all
this hardware is compatible with a modern out-of-the-box unpatched
linux distribution such as the Mandriva 2007 system I'm currently
using.

Thanks in advance. Cheers.
-Greg

On Thu, 28 Dec 2006 10:46:37 -0800, Greg wrote:

I've been running a mythtv htpc using a Hauppauge 350 for the last year
and been quite happy with it. One issue I've always had was that when I
watched TV through MythTV, the playback and audio were jerky. Though
when I watch a previously recorded program (usually with Kaffeine), the
playback is totally smooth.

I've been running MythTV for about a year with 4 HDTV cards in the master
backend which now is an X2 3800+ AMD, but before was a S754 A64 3000+.
I've got 2 other frontend machines. One is a S754 Sempron 2800+ with
another HDTV tuner in it (At under $20 each, why not) and the other is a
S754 Sempron 3100+. Each of these plays 1080i content HDTV just fine. I
can even get HD PNP on the X2 machine, but I never use it.

I'm guessing this is due to a limitation/bottleneck with my system.
* 3.6GHz P4 CPU
* 128Mb Radeon 9250 PCI video card
* 512Mb ECC DDR2-400
* 2x300Gb SATA-150
* 1280x768 @ 60hz output to my LCD TV * E7221 chipset * Mandriva 2007
OS
While I have plenty of CPU overhead, I'm guessing the bottleneck is the
old chipset and having to run my video through a PCI slot. (I don't
have a choice. Dell mutilated the PCI-E slot so you can't put a card in
it. The on-board graphics can't handle the resolution.) The specs on
the video card are 6.4Gb/s, comparable to low-end PCI-E cards (eg nvidia
7300GS). So, I'd bet my problem is with the chipset.

If the problem was a hardware problem, it would be there with the other
player. Until a few days ago, I had Mdv 2007 on the 2 frontends and they
played fine using the plf rpms. I've since switched them back to Knoppmyth
because I could get LIRC to work and my wife has to have her remote. In
any case, I suspect you just need to make some changes in playback options
of the frontend setup. Maybe check extra audio buffering, along with a
different codec and de-interlacing on/off. BTW, I'm using Nvidia FX5200
cards on the 2 frontends with or without XvMC assist. On the master
backend, I'm using the 6100 onboard video. Works fine.:-)

I recently added a HD5000 card to receive (H)DTV broadcasts and it has
the same live-playing jerkiness.

Before I drop cash to upgrade the system, I'm looking to see whether
there are any suggestions to improve watching the TV through MythTV.

I've been looking at upgrading to:
* E6700 Core 2 (I already have one!) * ASUS P5LD2 2.0 * 1Gb DDR2-533
* Radeon x550
The board and video card are older and lower-end, but I believe all this
hardware is compatible with a modern out-of-the-box unpatched linux
distribution such as the Mandriva 2007 system I'm currently using.

I'd go with an Nvidia video card. Maybe a 6200 if you want to stay cheap.
But I really think you can get what you have working ok. Just thought of
something. On the master I had to turn off sync to vblank using the
nvidia-settings for the driver I was using. It was choppy before that too.

--
Want the ultimate in free OTA SD/HDTV Recorder? http://mythtv.org
http://mysettopbox.tv/knoppmyth.html Usenet alt.video.ptv.mythtv
My server http://wesnewell.no-ip.com/cpu.php
HD Tivo S3 compared http://wesnewell.no-ip.com/mythtivo.htm

Wes Newell wrote:
On Thu, 28 Dec 2006 10:46:37 -0800, Greg wrote:

I've been running a mythtv htpc using a Hauppauge 350 for the last year
and been quite happy with it. One issue I've always had was that when I
watched TV through MythTV, the playback and audio were jerky. Though
when I watch a previously recorded program (usually with Kaffeine), the
playback is totally smooth.

I've been running MythTV for about a year with 4 HDTV cards in the master
backend which now is an X2 3800+ AMD, but before was a S754 A64 3000+.
I've got 2 other frontend machines. One is a S754 Sempron 2800+ with
another HDTV tuner in it (At under $20 each, why not) and the other is a
S754 Sempron 3100+. Each of these plays 1080i content HDTV just fine. I
can even get HD PNP on the X2 machine, but I never use it.

I'm guessing this is due to a limitation/bottleneck with my system.
* 3.6GHz P4 CPU
* 128Mb Radeon 9250 PCI video card
* 512Mb ECC DDR2-400
* 2x300Gb SATA-150
* 1280x768 @ 60hz output to my LCD TV * E7221 chipset * Mandriva 2007
OS
While I have plenty of CPU overhead, I'm guessing the bottleneck is the
old chipset and having to run my video through a PCI slot. (I don't
have a choice. Dell mutilated the PCI-E slot so you can't put a card in
it. The on-board graphics can't handle the resolution.) The specs on
the video card are 6.4Gb/s, comparable to low-end PCI-E cards (eg nvidia
7300GS). So, I'd bet my problem is with the chipset.

If the problem was a hardware problem, it would be there with the other
player. Until a few days ago, I had Mdv 2007 on the 2 frontends and they
played fine using the plf rpms. I've since switched them back to Knoppmyth
because I could get LIRC to work and my wife has to have her remote. In
any case, I suspect you just need to make some changes in playback options
of the frontend setup. Maybe check extra audio buffering, along with a
different codec and de-interlacing on/off. BTW, I'm using Nvidia FX5200
cards on the 2 frontends with or without XvMC assist. On the master
backend, I'm using the 6100 onboard video. Works fine.:-)

I recently added a HD5000 card to receive (H)DTV broadcasts and it has
the same live-playing jerkiness.

Before I drop cash to upgrade the system, I'm looking to see whether
there are any suggestions to improve watching the TV through MythTV.

I've been looking at upgrading to:
* E6700 Core 2 (I already have one!) * ASUS P5LD2 2.0 * 1Gb DDR2-533
* Radeon x550
The board and video card are older and lower-end, but I believe all this
hardware is compatible with a modern out-of-the-box unpatched linux
distribution such as the Mandriva 2007 system I'm currently using.

I'd go with an Nvidia video card. Maybe a 6200 if you want to stay cheap.
But I really think you can get what you have working ok. Just thought of
something. On the master I had to turn off sync to vblank using the
nvidia-settings for the driver I was using. It was choppy before that too.

--
Want the ultimate in free OTA SD/HDTV Recorder? http://mythtv.org
http://mysettopbox.tv/knoppmyth.html Usenet alt.video.ptv.mythtv
My server http://wesnewell.no-ip.com/cpu.php
HD Tivo S3 compared http://wesnewell.no-ip.com/mythtivo.htm

As a followup/closure for this thread, I did upgrade my system with the
above specs but went with an Nvidia 7300GT card. The TV viewing in
MythTV is now very smooth. I also had no trouble with the Mandriva 2007
detecting and properly installing the drivers for the board.

-Greg