That's the fun part in all this. I don't know. Back when the Alpha board was all the rage, Atarian Computing donated his board to me because he didn't have time to continue working on it. I never got it booting before H4 was on the horizon, so I set it aside. So the TOS chip I'm using is whatever he had on that board.
Since that variable is an unknown, I've got an exxos 102/104 chip in the mail, hopefully arriving sometime this week, and then at least we'll know.