Abstract: This discloses a memory module adapter card that allows newer dual in-line memory modules (DIMMs) to be used by computer system boards that were built to use older single inline memory modules (SIMMs) thereby permitting computer owners to update and upgrade older machines without modifying or changing their system boards. This memory module adapter card is designed to connect a memory DIMM inserted into a DIMM socket, carried thereon, to a pair of smaller SIMM sockets on a computer system board such that the DIMM appears to the computer as a pair of the smaller SIMMs that the board was originally designed for. This decreases the need for manufacturing and maintaining an inventory of the older SIMMs and provides owners of older computers the means to extend the useful life of their existing computer system even if the SIMMs designed for the computer no longer exist or are prohibitively expensive or very difficult to locate.