As portable computing devices get thinner and thinner, component manufacturers appear to be in a perpetual state of one-upmanship. In the latest round, Hitachi has put its HDDs on a crash diet and announced a range of super slim drives available in storage sizes up to 320GB. With a z-height of just 7mm (0.275 inch), the Z-series family of Travelstar and CinemaStar drives also offer low power consumption and low noise.

The new Z-series of HDDs from Hitachi Global Storage Technologies has upped the super slim storage bar somewhat by squeezing 320GB into a slender 7mm z-height, 2.5 inch drive. Designed as "a direct replacement for today’s standard 2.5-inch, 9.5mm hard drives" the new family of drives features common connectors and standard mounting points to help with integration into existing systems whilst also allowing the creation of new, slimmer and lighter device designs.

Leading the field is the speedy 7200RPM Travelstar Z7K320, which benefits from a 16Mb cache, low power draw (consuming 1.8W read/write and 0.8W idle) and low operating noise. The slightly slower 5400RPM Travelstar Z5K320 has an 8MB cache and even lower power consumption of 1.6W read/write and 0.55W idle. The 250GB and 320GB models in both families will be offered with enhanced-availability optimization, specially configured for applications needing constant access to data such as blade servers, network routers and compact RAID systems.

The Travelstar range is also available with optional hard drive level data protection in the form of self encrypting drive functionality. The drives support pre-boot authentication and have been designed to meet the Trusted Computing Group Opal Storage Security specification.

Optimized for audio and video devices such as set-top boxes and personal video recorders, the CinemaStar Z5K320 family is possibly the quietest spin around with an idle hum of just 1.9 bels (19dB) with seek only marginally louder at 2 bels (20dB). The drives spin at 5400RPM, have an 8MB cache, better protection against power fluctuation and enhanced Thermal Fly-Height Control for improved error rates.

Device manufacturers are currently sampling the new drives, which are scheduled for mass production in July and August. Expect to see them in new portable gadgets around then.