the present invention provides a memory system interface design , which provides access to a dual width memory bus . specifically , a subsystem and method provides for interfacing with a 32 bit or a 64 bit bus . the 32 bit bus would be used for low end products , and the 64 bit bus would be used for high end products . a memory control unit supports both the 32 bit and 64 bit modes . selecting a 32 bit or 64 bit memory subsystem gives a user more room to adjust system cost and performance .