I just want to clear up some points. The term '2GHz' is meaningless unless you give a processor. Multi-core will be faster than single-core. A Core2 will be slightly faster than an Ath64, which will be much faster than a P4. 'H.264' and even 'HD H.264' are equally ambiguous without knowing the encoding options. A 2GHz C2D will manage probably 18-20mbps H.264, or maybe 25mbps if it's encoded with CAVLC rather than CABAC. The problem with recordings off the HDPVR is that they are single-sliced, meaning you can only decode them with a single core, halving your performance. When/If the multithreaded ffmpeg stuff gets finalized and added into myth, a 2GHz C2D will have no trouble handling anything the HDPVR spits out.
Go ahead and delete this when you read it. --wagnerrp
Thanks for clarifying that. I really appreciate any help in getting a good background and getting up and running with DVRs. --trogod