Western Digital Caviar SE16 WD7500AAKS

WD Caviar SE16 WD7500AAKS Model Number Capacity WD7500AAKS 750 GB Lowest Real-Time Price: The race for the terabyte has come and gone. Laurels go to Hitachi for announcing (an easy feat) and eventually shipping (a more difficult accomplishment) the first, and so far only, 1000 GB unit. While the rumor mill is strife with word of terabyte product from other manufacturers, a pair of American firms have in the mean time set sight on a more attainable (both technologically and financially) 4-platter, 750 GB design. Seagate was first, delivering late last year the consumer-oriented Barracuda 7200.10 and enterprise-aimed Barracuda ES. More recently, Western Digital has finally updated its highly-regarded Caviar SE16 line to the larger 750 GB capacity. Although it rests in the ever looming shadow of the 1000-gig Deskstar, WD's announcement nonetheless caught the interest of many. Over the past couple years, with the introduction of the Caviar SE16 WD4000KS and RE2 WD4000YR, the firm's 7200 RPM SATA drives have earned a reputation of combining competitive performance with great environmental characteristics. And though Seagate's 750 GB Barracuda has been shipping for some time and though Hitachi's 7K1000 is also available in a 750 GB format, many readers have indicated that they'd like to see the newest offering from WD before committing to a platform for this generation.

The WD7500AAKS's basic specs are quite evolutionary. WD maintains the tried-and-true four-platter approach to achieve the drive's 750-gigabyte capacity. As has been the case with Caviar-style drives for years now, the firm specs the unit's average seek time at 8.9 milliseconds. Buffer size remains at 16 megabytes, standard for most of today's SATA units.

With this iteration, however, WD brings a couple new features to the table aimed at further refining reliability and power consumption. The first is an improved ramp load paradigm, a feature that parks the unit's read/write heads far away from delicate platters while the drive is powered off, ostensibly increasing non-operating shock resistance.

The WD7500AAKS's other newer feature is the company's "IntelliSeek" technology, a just-in-time approach that aims to minimize power draw. As we all know, today's hard drives feature rotating platters upon which hundreds of millions of individual sectors rest. In typical non-streaming use, data from a relatively small gathering of sectors is retrieved/written before the actuator then moves to the next group. Previous drives would maximize acceleration and deceleration of the actuator to get the read/write heads in place as quickly as possible.

Under the IntelliSeek paradigm, the drive moves the actuator just fast enough to get to the appropriate track as the target sector(s) approach the heads' location. This minimizes power draw with no hit to performance since the drive would have to wait until the appropriate data location rotated under the heads regardless of when the heads arrived in position. An analogy: consider an 11am hotel checkout and 1pm flight check-in. A traveler must leave the hotel by eleven and arrive by one, but can minimize the gasoline used by driving slowly... whether he gets to the gate by 11:30 or 12:59, he still boards the same flight and gets to his end destination at the same time.

In addition to contrasting the WD7500AAKS with all of today's leading 7200 RPM SATA drives, the following tests will also include WD's own 10K RPM Raptor. By virtue of its relatively limited capacity of 150 gigabytes, the drive's street price weighs in well under that of gargantuan 7200 RPM drives and thus merits inclusion in our charts: