【Hitachi】 DK3E1T-91 3.5-inch Hard Disk Drive

With a speed of 12,030 rpm, Hitachi’s DK3E1T-91 was the world’s fastest 3.5-inch hard disk drive when it was announced. It was designed for applications requiring high disk performance, such as UNIX / PC servers and disk array units.
The record-setting disk speed was achieved by using 2.5-inch disks in a 3.5-inch hard drive unit, and an access accelerator was used to reduce the average seek time to just 5 milliseconds. Furthermore, advanced signal processing technology raised the maximum data transfer speed to 27.3 MB per second.
Despite the drive’s higher performance, its read/write power consumption was just 11.8 watts — in the same vicinity as previous drives. This meant previous system enclosures and power supplies could be used without modification.

Specifications of the DK3E1T-91 hard disk drive
Introduced April 1998
Storage capacity per unit 9.2 GB
Recording density 173,300 bytes per inch
Track density 11,000 tracks per inch
Area recording density 1.9 Gbits per square inch
Number of disks 9
Number of heads 18
Average seek time Read: 5 ms, write: 6 ms
Disk speed 12,030 rpm
Data transfer speed 27.3 MB/s max.