Abstract: A data storage device is disclosed comprising a head actuated over a magnetic media comprising a plurality of data tracks, wherein each data track comprises a plurality of data sectors. A plurality of access commands are stored in a command queue, and an access command is selected from the command queue. When the selected access command is a write command to a target data track and at least part of a first data track proximate the target data track needs to be refreshed, a refresh read command is executed to read data from at least part of the first data track prior to executing the write command to the target data track.

Abstract: A spindle motor shaft having variable geometrical features for adjusting the torsion mode frequency of the shaft/stator assembly. The variable geometric features allow the torsion mode frequency to be tuned away from the driving force frequency of the motor. Variable geometrical features for the shaft may include circumferential grooves, radial slots cut through the shaft, or transverse holes disposed along the axis of the shaft. The radial slots have a longitudinal axis that is parallel to the axis of the shaft. Where circumferential grooves are used, the circumferential grooves may be designed to form a locator region along the shaft axis to promote axial alignment of the shaft and stator. Thermal track-misregistration (TMR) or screw torque problems are not introduced in the process of reducing or eliminating the acoustic problem thereby establishing a torsion mode frequency which is not subject to change due to temperature or time.

Abstract: Some disk drives produce a relatively large amount of acoustical noise. This noise is generated by vibrations of the disk drive cover caused by movement of the spindle motor and/or actuator head. A disk drive assembly is provided that significantly reduces the amount of acoustic noise emanating from a disk drive. An enclosure for a disk stack assembly, comprising at least one disk, mounted on a spindle attached to a motor and an actuator assembly, comprising at least one head attached to an actuator, is provided. The enclosure has an inner chamber with a post extending outwardly from a surface of the inner chamber. A compressible material is disposed at one end of the post abutting in a compressed state an opposing surface of the inner chamber. In a preferred embodiment, the post is integrally formed with the inner chamber and is unattached from the opposing surface. The damping post is preferably positioned in a position of maximum deflection for the vibration mode of the assembly.