TV Picture jumps

[jvb]

Area: My TV
MP Version: 0.1.3.0
Skin: mce
Windows Version: XP Home SP2
CPU Type: AMD Athlon 64 2800+
Memory: 512Mb PC3200
Motherboard Chipset: Biostar 210P SFF
Video Card: ATI Radeon 9250
Video Card Driver: Catalyst 5.1 (display driver version 6.14.10.6517)
Video Card Resolution: Any, e.g. 720*576
Video Render Type: Problem occurs with any render type
Video Codec Type & Version: problem occurs with any codec, e.g. MPeg2Dec
Audio Codec Type & Version: DScaler
TV Card: Hauppague WinTV Nova-T (newer version)
TV Card Type: DVB
TV Card Driver: 2.1

Synopsis: When watching live TV or a recording, every few seconds the tv stutters a little. If I use the XP Performance Monitor tool at the same time, I notice that the processor usage of the MediaPortal process goes up from 30% to 70-100%, and this coincides with the data bytes IO performance counter also shooting up to about 1 MB/s (again, measured against the mediaPortal process). My hard Disk is a Samsumg 80Gb Spinpoint (7200 speed) which should be ample.

[hmass]

I am getting a similar problem except stutter is a little less frequent. I'm running on an Athlon XP 2200 processor with 512Mb ram and a Radeon 9550 with 128Mb of memory. The problem was much worse on my old graphics card (a Geforce 4000MX 64Mb). I've been wondering for some time whether the limiting factor is the CPU or graphics card. The fact that you are suffering same problem with a more powerful machine but a lesser graphics card makes me wonder whether it is the graphics card that is the problem.

Any thoughts anybody?

Anybody know of a more powerful graphics card that is low profile and preferably fanless?

Thanks in advance.

[Taipan]

Guys,

Have you applied all the fixes and recommendations in the stickies in the Tips and Tricks forum - particularly #1 and #5?

Also, I recommend that you use the very latest ATI Radeon drivers, VMR9 Renderless and the Nvidia PureVideo decoder.

BTW, I use a Radeon 9550 with 128Mb RAM and it is fine - no stutter.

If you are watching DVB, are you sure that the "stutter" is not caused by a marginal TV signal? Does it occur on all channels, and does it occur with the DVB card's own application software?

[hmass]

Thanks for the tips, I had tried them except the nvidia decoder.
I think you are right about the marginal signal seems OK on ITV signals but poor on BBC - I am in a marginal area for reception.
My set top box picks up all stations without stutter 99% of the time, get very rare stutter when atmospherics aren't good. Guess I'll have to get a better aerial, as the TV card I'm using (Black Gold) is one of the more sensitive ones.
Building a Media PC is a never ending project isn't it!
Thanks again. :roll:

[jvb]

Thanks for the suggestions. I've tried the tips, and still have the problem. I think video playback is slightly smoother now, but I still get some jitter every few seconds, tied in with the spike in CPU usage by the MediaPortal process.

[jvb]

Brilliant!
Just found this thread:
http://nolanparty.com/mediaportal.so...pic.php?t=8251
and ran the registry entries listed there. TV picture has stopped jumping and CPU usage now about 25-30% when watching recordings.

[m0rt]

@jvb

You may have just saved me some money buying a new gfx card.
can't wait to get home and try out this registry hack.

Thanks jvb

[m0rt]

Fantastic!!

after I'd installed the m$ updates I found here http://nolanparty.com/mediaportal.so...pic.php?t=8146 and then added the registry entries I now have jump-free TV!! Thanks guys.

[daveyboy]

Just out of interest, what do people consider to be a marginal signal for DVB? My tv (built-in freeview) reports signal quality of between 50% and 70%, depending on the channel. I only notice the occasional green flash on the telly. I upgraded to shorter, high quality cables recently and got a 10-20% improvement.

But I get lots of skipping on the PC. Last night was particularly bad on Channel 4, but fine on the TV. WAF was way down Strangely on Wednesday I recorded a full half-hour program without a single skip, for the first time ever.

I'm going to try the fixes/reg entries etc. listed here to see if it makes a difference on the weekend. I might also try a more recent CVS build, see if the DVB problems have been resolved (currently using build from 11-11).

[daveyboy]

Update:

Installed all the updates mentioned here, along with the reg hack, latest ATI drivers and tried the PCI latency tool as well.

Sure enough, the latency for my gfx card was 255. Dropped it to 64 and noticed an immediate improvement! Was actually able to watch TV at last, and recorded several shows all of which played back with only the occasional skip (once every 10minutes on average).

Marvellous. WAF well up again!

On the down side, tried the latest CVS build as well, and performance was worse than ever. Lots of tearing whilst watching TV, and skipping continuously. I'll stick with my 11-11 build for now I think.