Definition – What does DDR (Double Data Rate) mean?
DDR stands of Double Data Rate is an advanced version of the SDRAM (Synchronous Dynamic Random Access Memory) a type of RAM. It can transfer data twice as fast as regular SDRAM chips. The difference between DDR and SDRAM is not the speed, but rather how many time data is transmitted with each per clock cycle, whereas SDRAM send signals per clock cycle. Both used frequencies, however, DDR uses both edges of the clock, whereas SDRAM uses only one. Double Data Rate is also known as dual pumped rate, double pumped rate or double transition rate.
Glossary Web explains DDR (Double Data Rate)
Mostly DDR is used in conjunction with microprocessors in order to carry data between the central processing units and North Bridge that is one of the two chips in the core logic chipset that is called the front side bus. Double Data Rate is also used for DDR SDRAM, Ultra-3 SCSI, HyperTransport Bus on AMD’s Athlon 64 processors. Double Data Rate has a memory clock speed of at least 200MHz, and quickly it becomes quite popular because it was quite cheaper and offer double the transfer rate and consumed less power them older SDRAM modules that expended 3.3 volts as compared to DDR’s 2.6 volts.