A dual inline memory module (DIMM) consists of a number of memory components (usually black) that are attached to a printed circuit board (usually green). The gold or tin pins on the bottom of the DIMM provide a connection between the module and a socket on a larger printed circuit board. The pins on the front and back of a DIMM are not connected to each other.
184-pin DIMMs are used to provide DDR SDRAM memory for desktop computers. Each 184-pin DIMM provides a 64-bit data path, so they are installed singly in 64-bit systems. 184-pin DIMMs are available in PC2100 DDR SDRAM or PC2700 DDR SDRAM. To use DDR memory, your system motherboard must have 184-pin DIMM slots and a DDR-enabled chipset. A DDR SDRAM DIMM will not fit into a standard SDRAM DIMM socket.