Abstract: A disk drive in a computer system is equipped with a power storage unit that supplies power to the drive controller when there is a system power interruption, such as a powerdown or a power failure. Once the controller is notified that system power has been interrupted, it will immediately initiate a seek to a reserved location in the disk drive and store the contents of the cache memory at the reserved location. After power has been restored to the system, the controller can load the contents of the reserved cylinders back to the cache memory and complete the pending write operations by writing all of the data items in the cache to their respective final locations in the drive.

Abstract: The present invention is drawn to an isolation system for separating two diverse fluid mediums from each other and, more particularly, an isolation system for prohibiting leakage of the diverse mediums around the peripheral surface of a piston movably mounted within a chamber. The present invention further relates to an improved multi-piston air-oil pressure intensifier employing the improved isolation system for separating and preventing leakage of the air and oil mediums during operation of the pressure intensifier.