In theory, the system should be able to use any size SIMM. In practice, many chipsets assume that 32M was as big as it was going to get (it probably seemed reasonable at the time :-))
I had one machine that registered the SIMMS as the wrong size and another that just puked on 64s. According to tech support (I bought one of the machines from Micron, who should know about memory), the system should have taken them.
In theory, there is no difference between theory and practice. In practice, there is...
I solved my problem by pitching the mom-board and replacing it with one that would take larger, cheaper DIMMs.
Regards,
Hugh