Just FYI in case it helps someone...
Problem with dropped frames on new machine. Old slower machine, same cable and camera worked fine. Swapped firewire cards, still worked and new machine didn't.
Most basics checked: separate 7200rpm capture drive defragged, nothing else running, network connections turned off, OCHI compliant firewire card, good firewire cable, etc. etc.
Disconnected Dazzle DVD Creation Station (USB), viola, no dropped frames.
On limited testing seems to have worked, not sure why, but it is a "capture" device and may have been causing some contention.