from my (limited) experience
Throughout this I have used either one or both Nebula PCI cards I have here.
I see a strong clean signal from CP on both BBC(554MHz) and ITV(522MHz)
I originally had a Mobile 2500+ with 2*256 DDR400 on a DFI mobo with a 6600TD
Tsreader streaming and Media Player Classic for the plackback using CoreAVC codec
Best I managed was 18-19 frames/sec when the CPU was overclocked from 1.8GHz to 2.2GHz using CoreAVC(Pdvd7 gave 12-13 frames/sec)
Since then I now use an Athlon 4200x2 dual core (not overclocked, CnQ enabled) on an Asus A8N-VM CSM mobo (using the onboard 6150 graphics) with 2*512 DDR400.
Now I get smooth play using TSreader/MPC/CoreAVC, but MPC appears to create temp files which when they reach ~4GB in size stop playback and MPC needs restarting
Now I'm trying DVBViewer V3.5.0 with the coreAVC codec. Last night this gave stuttering playback, but today it seems smooth(didnt change anything, left PC running overnight), although it has just frozen after approx 1hr 40m of the BBC preview prog. Just restarted DVBViewer and it seems smooth on BBC.
I use the 'jasorooneyhack' BDA drivers for the Nebula cards at present
The best setup I found for picture quality and smoothness was using tsreader and MPC, but the 4GB file issue means I only get around 20mins viewing (approx 11.5GB/hr) before it needs restarting which renders it unsuitable for watching footy.
I and others have searched for the answer, but cannot find one. Someone has posted on the MPC forum but has not had any replies as yet.
HTH
John