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Small circuit boards carrying memory integratedcircuits, with signal and power pins on both sides of theboard, in contrast to single-in-line memory modules (SIMM).The individual gold or lead connectors (pins) on SIMMs,although they are on both sides of the chip, are connected tothe same memory chip, while on a DIMM, the connections on eachside of the module connect to different chips. This allowsfor a wider data path, as more modules can be accessed atonce. DIMM pins are arranged in a zigzag design to allow PCBtracks to pass between them.The 8-byte DIMM format with dual-sided contacts canaccommodate 4- and 16-megabit dynamic RAM chips, and ispredicted to handle 64- and 256-Mbit devices. The 8-byte DIMMwill hold up to 32 megabytes of memory using 16-Mbit DRAMs,but with the 256-Mbit future-generation DRAM, it will be ableto hold a 64-Mx64 configuration. Another variation, the72-pin SO-DIMM, is designed to connect directly to 32 bitdata buses, and is intended for use in memory-expansionapplications in notebook computers.A Dual in-line memory module (DIMM), as opposed to SIMMs (usedby the majority of the PC industry) allows for a 128-bit datapath by interleaving memory on alternating memory accesscycles. SIMMs on the other hand, have a 64-bit data path.Suppliers are unanimous in their belief that the DIMM willeventually replace the SIMM as the market's preferred memorymodule.