DDR4
Memory Clock from 200-400MHz. Bus clock of 800-1600MHz. Data rate of 1600-3200 MT/s and a transfer rate of 12.8-25.6Gbps.
DDR3
Memory Clock from 100-266MHz. Bus clock of 400-1066MHz. Data rate of 800-2133 MT/s and a transfer rate of 6.4-17.066Gbps
DDR2
Memory clock from 100-266MHz. Bus clock of 200-533MHz. Data rate of 400-1066 MT/s and a transfer rate of 12.8-25.6Gbps.
DDR-200
Memory clock of 100 MHz. Bus clock of 100MHz. Data rate of 200 million transfers per second (MT/s) and a transfer rate of 1.6 Gigabits per second (Gbps).