With data being transferred 64 bits at a time, DDR SDRAM gives a transfer rate of ( memory bus clock rate ) × 2 ( for dual rate ) × 64 ( number of bits transferred ) / 8 ( number of bits / byte ).

With data being transferred 64 bits at a time, DDR2 SDRAM gives a transfer rate of ( memory clock rate ) × 2 ( for bus clock multiplier ) × 2 ( for dual rate ) × 64 ( number of bits transferred ) / 8 ( number of bits / byte ).

0.004 seconds.