Hybrid HDDs Make Gains, but Cache SSDs Reign Supreme: IHS

The proliferation of thin Ultrabook notebooks will keep cache solid-state drives as the storage market leader, IHS reports.

Cache solid-state drives will remain the mainstream storage solution for Ultrabooks and other super-slim notebooks, according to a new study from IT research firm IHS iSuppli. The study noted, however, that hybrid hard-disk drives, which contain a built-in layer of NAND flash memory, may offer the advantage of consolidated storage in the Ultrabook format, which is becoming increasingly popular as more advanced models from major vendors hit the marketplace.

Shipments of cache SSDs, which are employed as a separate memory component alongside an HDD (not together in one housing unit), are projected by IHS to rise to 23.9 million units this year, up by a whopping 2,660 percent from just 864,000 units in 2011. The research indicates the market has nowhere to go but up, with shipments jumping to 67.7 million units next year and crossing the 100 million-unit mark in 2015. By 2016, IHS is projecting shipments of cache SSDs will hit 163 million.

Meanwhile, shipments of hybrid HDDs are expected to double this year to 2 million, and will reach 25 million units by 2016. The report projected a third form of flash storage€”dedicated SSDs that contain no cache component€”would reach 18 million shipments this year in consumer applications, a figure that will ramp up gradually to 69 million units in 2016, as ultrathin notebooks continue to gain market share.

Hybrid HDDs consist of a traditional hard-disk drive and an integrated NAND flash layer within one self-contained form factor, like storage specialist Seagate Technology€™s Momentus XT hybrid product, up to 8GB of single-level-cell NAND and 750GB of memory on two 2.5-inch platters. Seagate is not alone in this market, with major rivals like Western Digital and Toshiba also planning hybrid HHDs containing 8GB or more of NAND cache.

€œThe cache SSD solution was first hit upon by PC manufacturers because the use of a dedicated solid-state drive proved too expensive when passed on to consumers in the retail market,€ Ryan Chien, an analyst for memory and storage at IHS, said in a prepared statement. €œHowever, a combined physical hard-disk drive with a smaller cache component allowed PC makers to reap the advantages of faster responsiveness and larger capacities while keeping costs down.€

However, the report notes there are roadblocks along the way to hybrid HHD adoption, despite the benefits of integrated components. €œCost concerns, longer design cycles and tighter engineering tolerances in the case of hybrid HDDs also add to their difficulty of use in Ultrabooks,€ the report concluded €œAs a result, the gain achieved through a consolidated form factor supposed to be a strength of hybrid HDDs will actually be a weakness in a few years as cache SSDs overcome that advantage. For their part, cache SSDs will remain as the favored storage solution in Ultrabooks, with penetration of the desktop and the rest of the notebook segments anticipated to follow.€