Hard disk drive with optional cache memory

摘要

A computer system includes a hard disk drive and an interface for optionally operationally connecting a cache memory for the hard disk drive, via a mechanism such as a system bus that is separate from the hard disk drive or directly to a controller of the hard disk drive. A hard disk drive of the present invention includes a nonvolatile medium for storing data, a controller for reading and writing the data and an interface for optionally operationally connecting to the controller a cache memory for the nonvolatile medium. Whether data are cached depends on whether the cache memory is present. Computer systems of the present invention are configured with or without cache memories, depending on customer requirements.