In a memory system having multiple memory sockets for removable insertion of memory modules therein, off-module data buffers are disposed in a data signaling data path between a memory control component and the memory sockets, and an off-module buffer controller is disposed in a control signaling path between the memory control component and the memory sockets. The off-module buffer controller receives control signals transmitted by the memory control component and re-drives/re-transmits the control signals to the memory sockets. The off-module buffer controller generates buffer-control signals in response to the control signals and outputs the buffer-control signals to the off-module data buffers to multiplex host-control-component access to the memory sockets.