I've got one of those G4 upgrades, a Sonnet (don't remember the specs; it was a score from right before I left for Europe so I didn't get a chance to play with it). It uses the early Power Mac's PDS, which of course nullifies the AV designation of those models. Of course, along with a good NuBus video card and an 8100/80 (with its 40MHz bus) to install them both into, it wouldn't be too bad of a combo.