hard drive history

transition: primitive ide drives

Seagate ST-157A

Photo: Red Hill.

Seagate ST-157A

The best of the IDE stepper generation, very reliable, and almost as fast as the Maxtor/Miniscribe one. These are instantly recognisable by their distinctive half-circle shape.

Seagate were very late entrants into the 3.5 inch drive market, having been distracted by their quality problems with the ST-251R, rapidly falling market share when the clone makers began to take over from IBM, and their acquisition of mainframe drive maker Imprimis, but when Seagate finally released 3.5 inch drives they were good ones. Most ST-157s were still going just fine when they were finally retired in favour of something much bigger and newer.

Data rate7.5 Mbit/secSpin rate3600 RPM
Seek time28msActuatorStepper
Platter capacity14.8MBInterfaceIDE mode 0
AT drive type2Form3.5" half-height
ST-157A44.4MB6 thin-film heads