A small outline dual inline memory module (SODIMM) consists of a number of memory components (usually black) that are attached to a printed circuit board (usually green). SODIMMs get their name because they are smaller and thinner than regular DIMMs. The gold or tin pins on the bottom of the SODIMM provide a connection between the module and a socket on a larger printed circuit board. The pins on the front and back of a SODIMM are not connected, providing two lines of communication paths between the module and the system.
200-pin SODIMMs are used to provide DDR SDRAM memory for laptop computers. Each 200-pin SODIMM provides a 64-bit data path, so they are installed singly in 64-bit systems. 200-pin SODIMMs are available in PC2100 DDR SDRAM. To use DDR memory, your system motherboard must have 200-pin SODIMM slots and a DDR-enabled chipset. A DDR SODIMM will not fit into a standard SDRAM SODIMM socket.