Original URL: http://www.theregister.co.uk/2012/09/13/hgst_helium_filled_disks/

HGST floats helium for low power, MASSIVE capacity HDDs

Up to seven platters in one drive

By Neil McAllister

Posted in Storage, 13th September 2012 22:28 GMT

A new hard drive technology from HGST promises to improve drive performance in virtually every category, the company says – including capacity, power, cooling, and storage density – all because the drives are filled with helium instead of air.

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

Campbell said the helium-stuffing technology has been under development at HGST – formerly Hitachi Global Storage Technologies and now a Western Digital subsidiary – for more than six years, but it's now mature enough that the company plans to release products based on it next year.

Helium fill has several advantages for hard disk drives. For starters, helium is only about 14 per cent as dense as air, which means it causes much less drag on the spinning platters. That in turn means the motor requires substantially less power to spin them. According to HGST, a helium-filled drive consumes about 23 per cent less power than an equivalent air-filled drive.

Customers can expect even greater power savings on a per-terabyte basis, though, because helium-filled drives can also deliver greater capacity. Owing to the lower fluid flow forces within a helium-filled disk, HGST says it can cram up to seven platters into a single 3.5-inch drive enclosure (up from the previous maximum of five), effectively bringing the watts consumed per terabyte down 45 per cent.

Those extra platters could also mean some seriously monster-sized drives. HGST hasn't teased any specs for the products it plans to bring to market in 2013, but given that it has already released a few 4TB drives using five-platter technology, it wouldn't be unreasonable to assume that its first seven-platter spinners will top out at 6TB or even larger.

HGST says helium is also a better thermal conductor than air and it produces lower shear forces, allowing helium-filled drives to run an average of 4 degrees Celsius cooler than air-filled ones, in addition to running quieter.

Taken all together, the advantages of helium-fill drive technology should allow modern, storage-hungry data centers to cram in more terabytes per square foot than ever before, which is good news for cloud service providers everywhere. The question that remains is what will it cost?

In addition to being easy to seal into a hard drive enclosure, air is plentiful and cheap. By comparison, helium is not. Although boffins say the visible universe is overflowing with the stuff – only hydrogen is more abundant – the actual supply of helium available on Earth is relatively miniscule, accounting for only 0.00052 per cent of the atmosphere by volume.

Helium is valuable enough stuff that in 1996, the US Congress voted to begin selling off its strategic helium reserve to industry as a way to raise some cash – a plan criticized by the US National Academy of Sciences, which worried that not enough new sources of helium are being located.

Exactly what this will mean for the prices of helium-filled drives as compared to air-filled ones is hard to say. HGST has said little about pricing, except that the new tech "will cost-effectively extend the capacity and cost-per-gigabyte curve for many product generations to come."

Given the declining price of solid-state storage, however, to say nothing of other efforts to increase the capacity of spinning-disk drives, it's safe to say that Hitachi's helium-filled drives won't be the only technology competing for data centers' storage buck next year. ®