Introduction

When Hitachi first announced the availability of the Deskstar 7K400 drive which comes with a whopping 400GB capacity, we thought it was the dawn of Hitachi's latest 100GB/platter technology. Little did we know that Hitachi was still using 80GB/platter disks, and it was with current technology that Hitachi was able to bring forth what is known today as the world's largest performance desktop hard disk drive.

Built with a total of five disks all packed into a standard height desktop drive, the Deskstar 7K400 operates with a total of 10 heads. This gives it a total of 400GB and it's Hitachi's boldest move ever since IBM's last attempt with the Deskstar 75GXP. Then, IBM broke the capacity record with 15GB/platter disks with the 75GXP using the same number of disks and heads as well.

The Deskstar 7K400's drive label. (Ed.: Some of our non-technical staff thought that the 400GB capacity was a misprint).

The bottom view of the drive.

The Deskstar 7K400 is not just your everyday desktop drive, but it has been designed with more than just the PC in mind. Targeting the consumer electronics market, the Deskstar 7K400 features what is known as the ATA Streaming Feature Set which Hitachi has helped developed for use in AV storage applications (such as digital video recorders, video editing or video streaming servers). The Streaming Feature Set includes five different components :-

Streaming Performance Log (to describe normal drive performance)

Error Recovery Time Limits (to prevent long delays for error recovery)

Continuous Read/Write Controls (to return/use partially correct data)

Streaming Error Logs (to reduce time delays for system error processing)

Configure Stream Command (to allow optimum drive buffer management)

These features were basically designed to enable smooth streaming of data when used in AV products. Since we know that video streams require a constant flow of data from the storage device, it is important that the storage device deliver these data smoothly, so that video recording/playback can continue without jerks or dropped frames. Even if the drive encounters slight errors, it would limit its recovery and would continue to send the data along with slight bit errors. According to Hitachi's white paper, the loss of a pixel is far better than the loss of an entire block of data, which would occur if the drive goes into multiple data recovery cycles. This technology is highly important in the use of HDTV recorders since high bandwidth streams are required. Without saying, it would be an important feature for AV system developers.

For PC users, the ATA Streaming Feature Set is not required since data accuracy is of higher importance.

The actual formatted capacity.