Double data rate (DDR) memory is coming. DDR2 is the name given to the latest memory technology used in IBM NetVista desktop PCs and IBM eServer xSeries servers.
The primary benefit is the potential for faster throughput. Currently DDR2 operates at data transfer rates starting at 400 MHz (the upper limit for DDR) and 533 MHz. Support for 667 MHz and 800 MHz transfer rate is expected in 2005. In addition, the DDR2 improves the power consumption of the DIMM because it works on a lower voltage. DDR operates at a range of 2.5 to 2.8 V, whereas DDR2 only requires 1.8 V.
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