IBM is launching two new families of Ultrastar 3.5-inch hard disk drives for the server market, including a 73-Gigabyte model which is the highest capacity currently available. The new products are: the ZX family, running at 10,000RPM and including the 73GB model, the 72ZX, and the LP family, which runs at 7,200RPM. The largest model in the ZX achieves an average seek time of 5.3 ms, while the other three in the range (the 36GB, 18GB and 9GB versions), achieve an average of 4.9 ms. The LP family, which has a different rotational speed and thus organizes the data differently, has an average of 6.8 ms.
John Fox, IBM’s product marketing manager for hard disk drives in Europe, explained that the former is aimed at the high-end, high-performance server market, while the latter is for use in what he termed the ‘value performance’ mainstream server segment. They are already shipping, and will progressively replace all the existing Ultrastar products being manufactured at the moment.
Both families contain the giant magnetoresistive head technology unveiled by IBM in late 1997. Fox added that they are also the only server drives currently on the market incorporating two other features. First are glass substrate media, which is considerably tougher than the traditional aluminum in use by other manufacturers. Secondly, they carry out the head load and unload functions away from the media, i.e. there is no contact with the actual media while they are taking place.
The ZX family of drives has an areal density of 7.04 billion bits per square inch, though IBM has already achieved a figure of 35 billion in the laboratory. Fox said that the technology can be expected to reach the market within two or three years.
