It is. I
own some three or four cards which have four 30-pin SIMM
sockets and are designed to plug into a 72-pin socket.
As I look at these, I
notice that they're all adapters as opposed to
something that gangs up multiple SIMMs to create a higher capacity
"SIMM". Anyone seen anything like that?
Um, that's exactly what mine do, unless I'm misunderstanding you. For
example, you can plug four 1M 30-pin SIMMs into one and you get a 4M
72-pin "SIMM".
A 1M 30 pin ZIMM has 1048576 locations each of 9 bits.
A 4M 72 pin SIMM has 1048576 locations each of 36 bits. It's electrically
much the same a 4 20 pin SIMMs. I suspect the adapter is just connectors
wired together in the right way.
I think what the first poster wants is a thing that takes 4 30-pin 1M
SIMMs and looks like a 4M 30 pin SIMM to the rest of the system. That is,
it appears to have 4194304 locations, each of 9 bits. It's not hard to
design something like that I think, but it would inovlve a few chips
-tony