would this be possible?
What are you asking? Please be a little more descriptive.
James M. Baker
Is that the question is:
"I put a G4 upgrade card in my G3. Can I add another G4 card and have a dual G4?"
In which case, the answer is:
If you are wanting to have dual processor G4s on your G3, then I'm pretty sure you may be able to. XLR8 made a dual socket ZIF card for the G3 Macs. It allowed you to add 2 g4 processors to your G3. I don't know if I've ever seen one of these. I'm pretty sure it was a real product though, because some XLR8 G4 upgrades at the time had a MPe desination. This supposedly meant that they could be used in a dual setup.
If you are wanting to have dual processor G4s on your G3, then I'm pretty sure you may be able to. XLR8 made a dual socket ZIF card for the G3 Macs.
Note that the card sold for between $800 and $1300 when new, so... good luck finding one. It also doesn't work with OS X.