I've just been dumbstruck dead. Did you look at the card list? It has one of the old Ithaca Audio CPU cards in it. The early IA Z80 cards were a poor second choice to a Cromemco card, but probably a step up from the original TDL Z80 card (that was the first Z80 CPU out). I had one of the IA cards, threw it away when they switched to Ithaca Intersystems and started making real class boxes and boards, got one of the XPU cards instead. Those were nice, 20 bit memory addressing with an MMU, very stable, it's what I use in my IMSAI now. And not even original MITS memory to go with it! Now if it had a working (!) 4K dynamic MITS RAM board I would be impressed. That was a truly rare commodity, because of design flaws the memory usually didn't (remember, that is). Jack Peacock