History (1994): 1GB Into 2.5-Inch HDD

More than 85% of all the HDDs sold today are in the 3.5-inch form factor. But the 2.5-inch ones, hardly only used in the notebook market, could slowly come and threaten them because their specs are getting closer.

They often offer a better shock resistance and their capacity is immediate: 810MB on 3 platters in its new DVAA 2810 ($795), 17mm high from IBM, compared to 4 platters and 19mm in MiniStor’s drive.

IBM reaches here 270MB per 2.5-inch platter, mainly on account of MR heads, this means a 493Mb areal density.

MiniStor (San Jose, CA), with its Japanese partner Hitachi has just set a 680MB record (12ms, $699). It is the only company to be involved in PCMCIA 1.8- and 2.5-inch HDDs.

Conner, Seagate and Western Digital had announced in 1992 1.8-inch units, all less than 65MB, but never went any further in their development.

MiniStor is also launching 340MB drives (12mm high, $499) and 510MB ones (19mm, $599) that were displayed for the first time by Hitachi at Comdex Fall in November 1993.

For the past two years, IBM’s Storage Systems Division (San Jose, CA) has systematically reacted to any announcement coming from its competitors that dare try to exceed the best it does in the 2.5 and 3.5-inch form factor. Big Blue’s answer to MiniStor is square inch. Big Blue also sets another record with a price lower than 1$/MB in a 2.5-inch disk drive. One gigabyte in such a small volume will certainly be reached before the end of the year.

A new technology that could become widespread has to be noticed on the DVAA 2810. Co-developed with Silicon Systems (Tustin, CA), IBM names it the No-ID format: the sector data preceding every block of data, is stored in solid-state memory, not on the disk itself, this allows a 10 to 15% gain in capacity on the media and improves the drive’s performances.

Still in the 2.5-inch form factor, Conner Peripherals (San Jose, CA) is the first to store such capacity, 350MB in a half-inch high device, the new Conner Filepro Notebook Low Profile 350 which only weighs 140 grams.

This article is an abstract of news published on the former paper version of Computer Data Storage Newsletter on issue 77, published on June 1994.