Promising faster responsiveness and performance, the use of cache solid state drives (SSDs) is set for explosive growth next year as the feature takes off in personal computing, according to an IHS iSuppli Storage Space market brief from information and analysis provider IHS.
Shipments in 2012 of cache SSD units are projected to reach 25.7 million units, up from just fewer than 900,000 units in 2011 when the technology first appeared. By next year, cache SSD shipments will amount to some 68.2 million units, on their way to approximately 121.0 million units by 2015.

The majority of cache SSD units will find their way into devices known as Ultrabooks—the super- thin mobile computers launched by chipmaker Intel Corp. in early 2011—even though non-Ultrabook desktops and notebooks also will account for cache SSD use. Of the more than 25 million cache SSDs to be shipped this year, about 22 million units will be present in Ultrabooks, up from a mere 500,000 last year. This means that cache SSD use in Ultrabooks this year will translate into a massive penetration rate of more than 75 percent, compared to a mere 12 percent in 2011.
A cache SSD drive looks like a regular solid state drive made up entirely of NAND flash. However, a cache SSD is not an independent storage drive and must run alongside a separate hard drive.
Essentially an Ultrabook requirement, cache SSDs make PCs more responsive, allowing faster boot- up times than hard disk drives. Cache SSDs are also less expensive than solid state drives, making them a more economical means to enhance system performance than by the wholesale replacement of hard disk drives with solid state drives. For instance, the Vertex 2 SSD from California-based OCZ Technology Group with 120 gigabytes costs about $160—the same price as Intel’s 311 Series cache SSD paired with a 500-gigabyte hard disk drive, suggestive of the kind of appeal that cache SSD solutions might offer for today’s price-conscious consumers.
Cache SSDs should prove popular likewise for enterprise notebooks, allowing for more notice- able performance improvements than a top-line processor or additional dynamic random access memory (DRAM). While prices for cache SSDs are still not low enough for widescale mainstream adoption, the next few years will see more pressure coming from Ultrabooks, along with even more affordable “smartbooks” that incorporate mobile architectures and low-cost operating systems, IHS believes.
A rival to cache SSD is the hybrid hard disk drive, which looks like a regular hard disk drive but uses embedded NAND as a cache on top of the usual DRAM cache. Both cache and hybrid drives have the option to utilize high densities of multilevel-cell (MLC) NAND, but only cache SSDs have an announced roadmap thus far. Being modular, cache SSD solutions also are inherently more robust and scalable when compared to the novel, one-piece nature of hybrid hard disk drives. The hybrid disk drive is an effort spearheaded by giant storage player Seagate Technology, exemplified by its Momentus XT product.
While cache SSDs had only a small presence in the storage industry in 2011, their impact in the com- ing years will become increasingly significant. In particular, the cache drive segment will be the primary reason behind the increased shipment growth of solid state drives, projected to jump to 46 million units this year, up from 17 million in 2011.
Read More > Ultrabook Clarity Strengthens Cache SSD Forecasts