EF51R Solid State Disk Drive

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EF51R
Manufacturer: Digital Equipment Corporation
Drive Controller(s): all DSSI Controllers
Capacity: 107 Mbytes (formatted)
Transfer Rate: 4.0 Mbytes/sec
Average Access Time: 0.25 msec
Start Time: < 2 min
Physical Size: 5.25" full height


The EF51R is the smallest drive of DEC’s first generation of solid state disks, packaged in a full-height, 5 1⁄4-inch form factor. The EF51R ISE provides non-volatility of data by a data retention system including:

  • Power sensing logic
  • An internal winchester magnetic disk drive
  • A battery to power the EF51R while dumping data to the winchester disk

Apart from the DSSI interface, the EF51R disk drive is identical to the EZ51R Solid State Disk Drive.

External links