AS of right this minute, you have two choices.
If buying a Quad you’ll need an HD PCIe card, since you’ll be working with HDV.
You can go with the Kona LHe or the Kona 3. The Kona LHe will better suit your HDV needs as it has analog component and analog inputs. The Kona 3 is a mostly digital i/o card, that has only analog component outputs.
Kona 3 also has an sd to hd upconvert function, the LHe does not. Both will down-convert. Neither card will cross-convert 720 to 1080i or 1080i to 720.
Blackmagic has a PCIe card, but it is an SD card only.
I currently have a Kona 2 with an io, and I can’t recommend aja products enough. They work and work well.
You might want to think about getting some fast storage such as a cheaper SATA RAID, or a more expensive fibre channel raid for increased reliability.
Good luck in your choices.
Jeremy
———–
G5 Dual 2Ghz <> 4GB RAM <> FCP 5.04 <> Kona 2
ATTO 42XS <> Huge Systems 4105 Fibre
OS 10.4.2 <> QT 7.0.3