Crucial 240-pin DIMMs are used in DDR3 memory for desktop computers. DDR3 features an improved architecture that allows it to transmit data more quickly. 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 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.Each 240-pin DIMM provides a 64-bit data path (72-bit for ECC or registered or Fully Buffered modules). (The Ballistix and Ballistix Tracer high-performance memory do not come in 72-bit or registered modules). Standard DDR3 240-pin DIMMs are currently available in PC3-8500 (DDR3 1066MHz) and PC3-10600 (DDR3 1333MHz) speeds. Additional speeds will be added as the technology becomes available.To use DDR3 memory, your system motherboard must have 240-pin DIMM slots and a DDR3-enabled chipset. This is because a DDR3 SDRAM DIMM will not fit into a standard DDR2 DIMM socket or a DDR DIMM socket.