Now that we have seen announcements of hybrid drives from Western Digital and Seagate, Toshiba arrives with a formal announcement of the product that was on display at last month’s Flash Memory Summit. Two 2.5″ Toshiba hybrid drives are starting to sample at 750GB and 1TB capacities. Both have 8GB NAND caches, 6Gb/s SATA 3 interfaces, and 5,400RPM spindle speeds. They are both built using 32nm SLC NAND, Toshiba’s “generation before last” technology, preceding the 24nm and 19nm nodes shipping in high volume today.
More importantly, both are 9.5mm in height, a thickness that renders them difficult to incorporate into the 18mm maximum thickness of the smaller Ultrabooks – a notebook form factor that Intel is heavily promoting.
How is this whole market going to settle? In Objective Analysis‘ report on hybrid drives: Are Hybrid Drives Finally Coming of Age? we postulate that hybrid drives could rapidly move in to displace standard HDDs the same way that HDDs incorporating DRAM caches displaced cacheless HDDs in the middle 1990s. (This report can be purchased for immediate download on our website.)
In an equally likely alternative scenario, variable-capacity SSDs or even NAND modules could be paired with standard HDDs, eliminating any need for NAND on the HDD itself. One attraction to this outcome is that a varying amount of cache can be used without the HDD maker or PC OEM having to inventory every possible combination of HDD and NAND capacities.
Of course, the market could support a combination of both scenarios – it does this today with DRAM main memory working in conjunction with an HDD that incorporates a DRAM cache. Should hybrid drives take this route The SSD Guy would expect them to eventually use a single NAND chip at the lowest density (and lowest price) the NAND makers are willing to produce.
