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Hard Disk 20

The Macintosh Hard Disk 20 is the first hard drive developed by Apple Computer specifically for use with the Macintosh 512K. Introduced on September 17, 1985, it was part of Apple's solution toward completing the Macintosh Office (a suite of integrated business hardware & software) announced in January 1985. It would be over a year more before Apple…

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Connection
Floppy drive port at 500 kbit/s
Connects to
DB-19 Connector
Cost
US$1,495 (equivalent to $4,475 in 2025)
Design firm
Apple Inc.
Dimensions
3.1 x 9.7 x 10.5 inches (7.9 x 25 x 27 cm)
Discontinued
September 1987 (1987-09)

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Overview

Features

History

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Hard Disk 20

Nodes28
Edges27
Triples77
Avg. degree1.93
Density0.071429
Components1

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Hard Disk 20

Top relations

related to Features · 28
Hard Disk 20 → Apple, Apple's, Apple's HD20, As, At, Finder, Hard Disk, HD20, Hierarchical File System, In, It, Mac, Macintosh, Macintosh File System, Macintosh Plus, MB, RAM, Rodime, ROM, Serial Port
related to history · 23
Hard Disk 20 → Apple, Apple-manufactured, April, Hard Disk, HD20, HD20's, However, In, January, Macintosh, Macintosh II, Macintosh Plus, Macintosh XL, Macs, Only Macs, Rodime, ROM, Sales, SCSI, Some
related to External links · 13
Hard Disk 20 → Classic Macintosh Preservation, Disk, February, Hard Disk, Info, Mac Systems Compatible, Mac512, May, System, The M0001 Registry Owners, Vintage MacintoshApple Macintosh Before, VintageMacWorld, Wayback Machine
Connection · 1
Hard Disk 20 → Floppy drive port at 500 kbit/s
Connects to · 1
Hard Disk 20 → DB-19 Connector
Cost · 1
Hard Disk 20 → US$1,495 (equivalent to $4,475 in 2025)
Design firm · 1
Hard Disk 20 → Apple Inc.
Dimensions · 1
Hard Disk 20 → 3.1 x 9.7 x 10.5 inches (7.9 x 25 x 27 cm)
Discontinued · 1
Hard Disk 20 → September 1987 (1987-09)
Introduced · 1
Hard Disk 20 → September 17, 1985 (1985-09-17)

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Important terminology

macintosh hard disk hd20 apple drive 20 system file floppy introduced scsi use drives computer 512k apple's january port inc

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Hard Disk 20ConnectionFloppy drive port at 500 kbit/s1.00infobox
Hard Disk 20Connects toDB-19 Connector1.00infobox
Hard Disk 20CostUS$1,495 (equivalent to $4,475 in 2025)1.00infobox
Hard Disk 20Design firmApple Inc.1.00infobox
Hard Disk 20Dimensions3.1 x 9.7 x 10.5 inches (7.9 x 25 x 27 cm)1.00infobox
Hard Disk 20DiscontinuedSeptember 1987 (1987-09)1.00infobox
Hard Disk 20IntroducedSeptember 17, 1985 (1985-09-17)1.00infobox
Hard Disk 20ManufacturerApple Inc.1.00infobox
Hard Disk 20Memory20 MB1.00infobox
Hard Disk 20Power consumption30 W1.00infobox
Hard Disk 20TypeHard Disk1.00infobox
Hard Disk 20Weight7 lbs (3.2 kg)1.00infobox
Hard Disk 20is afirst hard drive developed by Apple Computer specifically for use with the Macintosh 512K0.90text

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