I ask purely out of academic curiosity, as my Quadra 840av has either 48 or 64 MiB in it now, don't recall which, which I am in no danger of getting close to the edges of either way. 128 megs is as big as a _single_ 72-pin SIMM can get, so why doesn't this machine support anything over 32MiB times 4? Is it just a ROM limitation, or is it like my Classic II in that the various motherboard components literally can't address anything past an arbitrary limit?