【NEC】 DVF4400S

NEC announced the DVF4400S 3.5-inch magnetic disk unit intended for high-end systems in March 1996. The DVF4400S recorded about 900 MB of data per disk, the largest per-disk recording capacity in the world, and housed five disks for a total recording capacity of 4.4 GB.

By using an MR recording head for higher recording densities and PRML, a demodulation method for higher read efficiencies, NEC nearly doubled the per-disk recording capacity over existing models to 900 MB, which was the largest capacity in the world. The DVF4400S worked with many different computer products because it had three SCSI interfaces — Standard, Wide, and Ultra — and an attachment that combined the power connector and interface connectors into a single connector. NEC also doubled the maximum host transfer speed to 40 MB per second by reducing the average read seek time to just 8 milliseconds and increasing the fastest read / write speed to 14.5 MB per second, which was the fastest in the world at the time.

Specifications of the DVF4400S magnetic disk unit
Storage capacity [GB] 4.4
Average seek times [ms]

Average rotational latency [ms] 4.17
Data transfer speeds [MB/s]
Read / write speed
Host transfer speeds
(Standard / Wide / Ultra)
Disk diameter [inches] 3.5
Number of disks 5
Number of data recording heads 10
Disk rotational speed [rpm] 7,200
Recording density [bytes/inch] 117,000
Track density [tracks/inch] 6,100
Recording format 8-9PRML
Overall external dimensions [mm] 101.6 x 145.8 x 25.4 (w x d x h)