US Patent 8495276 Power saving optimization for disk drives with external cache

A power conservation system implementable in a computer system. The system includes a non-volatile cache memory (NVCM) device for storing information. The NVCM device is operationally coupled to the computer system. The system also includes a data storage device coupled to the NVCM device. The data storage device is for storing said information. The system further includes a controller coupled to the NVCM device. The controller initiates an occurrence of writing the information in the NVCM device to the data storage device. The occurrence of writing causes powering up of the data storage device to which the data is to be written or from which data is to be retrieved.