[mythtvnz] DVB-T signal strength and CPU usage

[Graeme Woollett]

I got Freeview HD going on my myth box last night, it has an dual core 
3600+ AMD processor.
There are times where the video is shudder free and others where it 
seems to struggle.  Most of the time the CPU is sitting at 103% usage.

What is a acceptable signal strength?  I have 22% and 4 ish db which 
seems very low.
I have only had success watching the TVNZ multiplexes, no luck with TV3, 
C4 etc.  They are detected but no lock.

Also are there low cost NVidia based graphics cards that people know of 
that have a SPDIF input for injection into the HDMI cable?
I have a 8600GT card in another PC that has it, but I'm  hoping not to 
spend  as much as that cost...

Thank you Paul and others for the huge amount of work you have put in, 
it's much appreciated! :-)