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There are two different strategies employed in dual-channel memory controllers, with the first being a platform with two independent channels in hardware. This is the format of Nvidia's nForce and nForce2 chipsets for AMD Athlon XP systems, where each memory bank has its own memory channel and an arbiter distributes the load between them and plays traffic cop for incoming data.

This has the benefit of high actual memory bandwidth, but comes at the cost of some system overhead or latency associated with the arbiter (a matter addressed or greatly reduced by the nForce2), along with greater limitations on installed memory. With the nForce2, for instance, sticking with two memory modules is the best option for full dual-channel performance and stability.

The second strategy is to actually create a wider memory channel, thereby "doubling up" on standard DDR's 64-bit data paths. This is common of Intel dual-channel memory controllers. In the case of the E7205 workstation chipset (diagrammed below), each pair of installed modules acts as a 128-bit dual-channel memory module, which can transfer twice as much data as a single-channel solution, with no need for an arbiter. Depending on the application, this solution may not be as flexible as two hardware channels, and it does require an innovative chipset design to handle the 128-bit incoming data streams.