While the contacts on SIMMs on both sides are redundant, DIMMs have separate electrical contacts on each side of the module. DIMMs began to replace SIMMs (single in-line memory modules) as the predominant type of memory module as IntelP5-based Pentium processors began to gain market share. These modules are mounted on a printed circuit board and designed for use in personal computers, workstations and servers. Three SDRAM DIMM slots on a computer motherboardĪ DIMM or dual in-line memory module comprises a series of dynamic random-access memoryintegrated circuits.