DDR (double data rate) SDRAM is the latest evolution in random access memory (RAM) technology. All SDRAM operates on a system frequency or "bus" speed measured in mega hertz (MHz). Traditional SDRAM used only the rising edge of the clock cycle to transfer data. The new DDR SDRAM transfers data on both the rising and falling edge of the clock. PC3000 is the common name for the JEDEC specification for DDR which runs on a 183MHz bus speed (366MHz double data rate). The chips themselves are named in a more conventional way as "DDR-366" where the name reflects their MHz speed. The modules, however, are named for the effective data transfer of 3000 MB/sec (3.0 GB/sec) on a 64-bit bus.PC3000 DDR uses DDR-366 chips. These modules are programmed for CAS 2.5-3-3 operation at 366MHz via the serial presence detect (SPD) EEPROM. PC3000 DDR is designed for use with motherboards supporting the PC3000 spec and CPUs which run on a 133MHz FSB (266MHz DDR) and yet to be released CPUs running on a 183MHz FSB (366MHz DDR).This PC3000 module is an unbuffered 184-Pin Double Data Rate (DDR) Synchronous DRAM Dual In-Line Memory Module (DIMM), organized as a dual-bank high-speed memory array. Organized as 64Mx64, this module is a two-bank DIMM that uses sixteen 32Mx8 DDR SDRAMs devices in 400 mil TSOP packages. The DIMM achieves high-speed data transfer rates of up to 366MHz.