No. Under this explicit mapping they select different banks. Decode the actual controller mapping before explaining locality or conflicts.

Common trap: Giving a generic fix without identifying the boundary and unmet obligation in this example.

The width-and-transfer-rate product is only a ceiling. Refresh recovery, command timing, bank and row state, read/write turnarounds, request granularity, controller policy and competing traffic can all reduce accepted useful bytes. Quantify their effect with the selected device mode and a stated workload; no single efficiency percentage applies to every DDR system.

Common trap: Multiplying width × frequency only.