updated 08:52 pm EDT, Thu September 13, 2012
Gas replacement lowers drive power, temperature
Western Digital plans to ship hard drives filled with helium instead of air, starting from next year. Hitachi Global Storage Technologies (HGST), bought by Western Digital last year for $4.3 billion, believes the change to helium will help significantly reduce the total cost of ownership (TCO) of drives in businesses running their own data centers.
By replacing the air with helium, a gas that is one-seventh the weight of air, there is less drag force acting on the spinning disk stack inside the drive, which in turn lowers the need for more power by the motor. The lower density also allows for more platters to be stacked into the same drive, by moving the platters closer together and also reducing the distance between data tracks. The more efficient thermal conduction of helium leads towards a cooler drive as a whole, and potentially less noise.
Current tests by HGST show a helium-filled drive having a 23 percent reduction in power consumption compared to a similar specification air-filled drive, a 45 percent improvement in watts-per-TB, and operating four degrees Celsius cooler. It has taken the company six years to reach the point where it can be introduced into the market, however it is unlikely to appear in drives typically bought by home users until long after businesses models have been available.