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IBM System/360 Model 25

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IBM System/360 Model 25
ManufacturerInternational Business Machines Corporation (IBM)
Product familySystem/360
Release dateJanuary 4, 1968 (1968-01-04)
Introductory price$253,000 ($5,330/month)
(typical configuration)[1]
DiscontinuedOctober 7, 1977
Memory16 - 48K Core
WebsiteOfficial website IBM Archives

The IBM System/360 Model 25 was an IBM mainframe from the System/360 line.


History

At a time when lower priced [2] alternatives [3][4] were available, this model provided a stop-gap measure.[2]: "retain for IBM..." 

It was introduced in 1968,[5] 3 years before the IBM System/360 Model 22;[6] both were withdrawn on the same[7] day.

Models

Somewhat like the IBM System/360 Model 30,[8] four models were offered, configured with 16K, 24K, 32K or 48K of core memory.[5]

System configuration

Most unusual about the 360/25 was a feature somewhat analogous to the IBM System/360 Model 44's integrated single disk storage drive, namely an integrated attachment.[9]

The standard set of peripherals[5] was available, although by this time customers had found their way to IBM-compatible alternatives.[10][11]

References

  1. ^ including at least twice the memory of the 360/30
  2. ^ a b Computerworld,Sept.5,1977,p.40 - an IBM task force report said that a then-planned model 25 would "retain for IBM many installations exposed by price alone rather than by price/performance."
  3. ^ Service Bureaus: By 1968, there were 32 such service bureaus serving the US National Institutes of Health (NIH) alone - "Information Technology Corporate Histories Collection". Computer History Museum. http://www.computerhistory.org/corphist/view.php?s=stories&id=136.
  4. ^ Prior generation systems: Honeywell 200, a competitor to IBM's own IBM 1401.
  5. ^ a b c https://www-03.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP2025.html
  6. ^ https://www-03.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP2022.html
  7. ^ 1977
  8. ^ initially 8K, 16K, 32K, 64K; subsequently a 48K offering followed
  9. ^ "IBM System/360 Madel 25 Functional Characteristics" (PDF). IBM. January 1968. A24-3S10-0.
  10. ^ Computerworld,Aug. 18, 1980, p. 7, Storage Technology
  11. ^ Computerworld,July 2, 1979, p. 5, Control Data Corporation
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