Dual channel describes a technology that theoretically doubles data throughput from the memory to the memory controller.

Dual channel is the ability that some memory controllers have to expand the width of their data busses from 64 to 128 bits. Considering that everything remains the same (clock speed, ….), the memory maximum theoretical transfer rate is doubled by the use of this technique.

Think of it as a road intersection. The memory controller is the traffic light. In one direction you have a nice four lane road going through the light. One way goes to the CPU and the other goes around the board to where it is needed, such as the video card. There is another way to go, and that is to the memory. In single channel, this isn’t pretty. It’s a one lane street which needs to send information both directions. With dual channel it is a little bit easier. It could now be a two lane road, to send and receive at the same time.