Signals A[0] - A[12] and BA[0] - BA[1] on each RAM DIMM make up a 15-bit multiplexed address bus that can support several different types of SDRAM devices. Table 4-2 lists the types of devices that can be used in the iMac by size, configuration, and sizes of row and column addresses.
IMPORTANT
The iMac supports only the types of SDRAM devices listed in Table 4-2 . Other types of DRAM devices should not be used with this computer.