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. 184-pin DIMMs are used to provide DDR SDRAM memory for desktop computers. Standard 184-pin DIMMs are available in PC1600 DDR SDRAM, PC2100 DDR SDRAM, PC2700 DDR SDRAM, & PC3200 DDR SDRAM. To use DDR memory, your system motherboard must have 184-pin DIMM slots & a DDR-enabled chipset. A DDR SDRAM DIMM will not fit into a standard SDRAM DIMM socket. (Information about which memory technology your system uses is included in the Crucial Memory Advisor tool.) The number of black components on a 184-pin DIMM can vary, but it always has 92 pins on the front & 92 pins on the back, for a total of 184. 184-pin DIMMs are Approx. 5.25 inches long & 1.25 inches high, though the heights can vary. While 184-pin DIMMs & 168-pin DIMMs are Approx. the same size, 184-pin DIMMs have only one notch within the row of pins