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 pins on the bottom of the DIMM provide a connection between the module & a socket on a larger printed circuit board. The pins on the front & back of a DIMM are not connected to each other.240-pin DIMMs are used to provide DDR2 SDRAM memory for desktop computers. DDR2 is a leading-edge generation of memory with an enhanced architecture that allows it to transmit data very fast. Each 240-pin DIMM provides a 64-bit data path (72-bit for ECC or registered or Fully Buffered modules). (The Ballistix & Ballistix Tracer high-performance memory do not come in 72-bit or registered modules). Standard DDR2 240-pin DIMMs are available in DDR2 PC2-3200 SDRAM, DDR2 PC2-4200 SDRAM, DDR2 PC2-5300 SDRAM & PC2-6400 SDRAM.