The SIMMs are 168-pin, JEDEC-standard devices. Do not use other types of memory modules.
Requirement - Do not mix 8, 32, or 128 Mbyte SIMMs in the same bank. (All SIMMs in a bank -- eight SIMMs -- must have the same capacity.)
Note that two banks of SIMM slots on a CPU/Memory+ board are interleaved. A bank is composed of eight alternating SIMM slots.
All SIMMs in a bank should have the same speed rating. If SIMMs of different speeds are mixed in a bank, the bank will function, but at the lowest speed.