A memory unit includes a system memory controller coupled to a plurality of memory clock oscillators and a plurality of respective voltage controllers, wherein each memory clock oscillator and respective voltage controller are coupled to a memory receptacle and thus provide a plurality of memory receptacles, each receptacle in the plurality of receptacles having a separate power boundary for operation of a memory type. The memory unit provides a computing system with capabilities to operate a variety of memory types. Methods and computer program products of operation of the memory unit are provided.