A circuit is configured to be mounted on a memory module connectable to a computer system so as to be electrically coupled to a plurality of memory devices on the memory module. The memory module has a first number of ranks of double-data-rate (DDR) memory devices activated by a first number of chip-select signals. The circuit is configurable to receive bank address signals, a second number of chip-select signals, and row/column address signals from the computer system. The circuit is further configurable to generate phase-locked clock signals in response to clock signals received from the computer system and to provide the first number of chip-select signals to the first number of ranks in response to the phase-locked clock signals, the received bank address signals, the received second number of chip-select signals, and at least one of the received row/column address signals.