hard drive history


revolutions: 3600 > 4500 > 7200 rpm

IBM DALA-3540

Photo: Red Hill.

IBM DALA-3540

These were an excellent little drive; very fast for a 500, as reliable as sunrise, and delightfully easy to work with. They were the only 500MB drive we ever sold in preference to the bulletproof Seagate Medalist 545.

The DALA-3540 was the first mass-market drive to use Magneto-Resistive head technology, and had only a single platter — very unusual in a 540MB drive.

As you can see from the illustration, there was ample room inside the HDA to put a second platter, but IBM did not trouble to do the obvious and produce a 1.08GB version of the DALA, presumably because that would have competed too closely with the 5400 RPM Deskstar XP (which also used MR heads and 540MB platters).

By the time the DALA-3540 arrived, 500MB was entry-level and the higher-spec systems were shipping with larger drives, so most of our DALAs went into budget-oriented 486DX/2s and DX/4s which, thanks to excellent hard drive performance, remained useful longer than might have been expected otherwise.

Performance0.78ReliabilityAAA
Data rate49 Mbit/secSpin rate4500 RPM
Seek time12msBuffer64k
Platter capacity270MBEncodingRLL
Form3½" 1/3 heightInterfaceIDE mode 3
DALA-3540540.8MB2 MR heads****