The normal limit of five disks per drive is completely bypassed

Sep 13, 2012 12:50 GMT  ·  By

HGST, formerly Hitachi Global Storage Technologies and now a Western Digital company, won't win any prices for compactness thanks to its latest hard drive technology.

Then again, that was never the point. Rather than the consumer segment, HGST looked at the needs of the enterprise and cloud data center market.

One major design shift is that HGST has departed from the standard 3.5-inch drive model, exceeding the 5-platter limit. Each drive now has seven disks.

Another major difference is that, instead of air, the HDD is filled with helium, whose mass is one seventh of air mass.

The lower density and, thus, lower drag force cuts down the requirements for motor mechanical power. In addition, it allows to place the disks closer together. Air normally buffets the disks and the arms hard enough to make this unsafe.

Furthermore, helium brings lower shear forces and more efficient thermal conduction, which makes drives more silent and cooler. The reduction in total cost of ownership (TCO) is just a side benefit.

“The benefits of operating a HDD with helium fill have been known for a long time. The breakthrough is in the product and process design, which seals the helium inside the HDD enclosure cost effectively in high-volume manufacturing,” said Steve Campbell, chief technology officer at HGST.

Helium-filled drives are said to use 23% less power than an equivalent air-filled unit, and that's when not accounting for the higher capacity. When the two extra platters are factored in, the difference becomes 45%. Further development could widen the gap even more.

HGST will begin shipping helium-filled HDDs in 2013 (next year). Unfortunately, that means that capacities and product specifications will be a secret until then.

"Our new breakthrough platform delivers unprecedented innovation with new features optimised to meet the performance, scalability, efficiency and TCO demands of both corporate and cloud datacentres, which could not be achieved using conventional techniques,” said Mike Cordano, president of HGST.

“With these improvements, customer interest has been positive and we look forward to qualifying our new drives in 2013.”