Editing IBM System/370 (section)

====System/370-compatible====
Beginning in 1977, IBM began to introduce new systems, using the description "A compatible member of the System/370 family."<ref name="IBM.3031">{{cite web|url=https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3031.html|title=3031 Processor Complex|website=IBM Archives|date=23 January 2003|publisher=IBM|archive-url=https://web.archive.org/web/20230719144802/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3031.html|archive-date=2023-07-19|url-status=dead}}</ref><ref>{{cite web|url=http://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_basinfo.html|title=Mainframes - Basic information sources|website=IBM Archives|date=23 January 2003|publisher=IBM|archive-url=https://web.archive.org/web/20230922112055/http://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_basinfo.html|archive-date=2023-09-22|url-status=dead}}</ref>

=====IBM 303X=====
{{main article|IBM 303X}}

The first of the initial high end machines, IBM's '''3033''', was announced March 25, 1977<ref>{{cite web|url=https://www.ibm.com/ibm/history/exhibits/3033/3033_PR01.html|title=3033 Press announcement|website=IBM Archives|date=23 January 2003|publisher=IBM|archive-url=https://web.archive.org/web/20230719145845/https://www.ibm.com/ibm/history/exhibits/3033/3033_PR01.html|archive-date=2023-07-19|url-status=dead}}</ref> and was delivered the following March, at which time a multiprocessor version of the 3033 was announced.<ref>{{cite web|url=https://www.ibm.com/ibm/history/exhibits/3033/3033_PR02.html|title=3033 Multiprocessor - Press announcement|website=IBM Archives|date=23 January 2003|publisher=IBM|archive-url=https://web.archive.org/web/20230719223056/https://www.ibm.com/ibm/history/exhibits/3033/3033_PR02.html|archive-date=2023-07-19|url-status=dead}}</ref> IBM described it as "The Big One."<ref>{{cite web|url=https://www.ibm.com/ibm/history/exhibits/3033/3033_intro.html|title=IBM's 3033 "The Big One": IBM's 3033|website=IBM Archives|date=23 January 2003|publisher=IBM|quote=''THINK'' magazine later simply dubbed it {{ndash}} "The Big One."|archive-url=https://web.archive.org/web/20230928083308/https://www.ibm.com/ibm/history/exhibits/3033/3033_intro.html|archive-date=2023-09-28|url-status=dead}}</ref>

IBM noted about the 3033, looking back, that "When it was rolled out on March 25, 1977, the 3033 eclipsed the internal operating speed of the company's previous flagship the System/370 Model 168-3 ..."<ref name=FLAG3/>

The IBM '''3031''' and IBM '''3032''' were announced Oct. 7, 1977 and withdrawn Feb. 8, 1985.<ref name="IBM.3031"/><ref>{{cite web|url=https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3032.html|title=3032 Processor Complex|website=IBM Archives|date=23 January 2003|publisher=IBM|archive-url=https://web.archive.org/web/20230719144906/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3032.html|archive-date=2023-07-19|url-status=dead}}</ref>

=====IBM 308X=====
{{main article|IBM 308X}}

Three systems comprised the next series of high end machines, IBM's 308X systems:
* The '''3081'''<ref name="IBM.3081">{{cite web|url=https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3081.html|title=3081 Processor Complex|website=IBM Archives|date=23 January 2003|publisher=IBM|archive-url=https://web.archive.org/web/20230719144956/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3081.html|archive-date=2023-07-19|url-status=dead}}</ref> (announced Nov 12, 1980) had 2 [[Central processing unit|CPU]]s
* The '''3083'''<ref name="IBM.3083">{{cite web|url=https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3083.html|title=3083 Processor Complex|website=IBM Archives|date=23 January 2003|publisher=IBM|archive-url=https://web.archive.org/web/20230719144956/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3083.html|archive-date=2023-07-19|url-status=dead}}</ref> (announced Mar 31, 1982) had 1 CPU
* The '''3084'''<ref name="IBM.3084">{{cite web|url=https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3084.html|title=3084 Processor Complex|website=IBM Archives|date=23 January 2003|publisher=IBM|archive-url=https://web.archive.org/web/20231210232532/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3084.html|archive-date=2023-12-10|url-status=dead}}</ref> (announced Sep 3, 1982) had 4 CPUs

Despite the numbering, the least powerful was the 3083, which could be field-upgraded to a 3081;<ref name="IBM.3083"/> the 3084 was the top of the line.<ref name="IBM.3084"/>

These models introduced IBM's [[31-bit|Extended Architecture]]'s 31-bit address capability{{sfn|S370-XA-1st}} and a set of [[Backward compatibility|backward compatible]] MVS/Extended Architecture (MVS/XA) software replacing previous products and part of OS/VS2 R3.8:
{| class="wikitable"
|-
! Number
! style="align:left;" | Name
|-
| 565–279
| Basic Telecommunications Access Method/System Product (BTAM/SP)
|-
| 5668–978
| Graphics Access Method/System Product (GAM/SP)
|-
| 5740-XC6
| MVS/System Product - JES2 Version 2
|-
| 5685–291
| MVS/System Product - JES3 Version 2 
|-
| 5665–293
| TSO Extensions (TSO/E) for MVS/XA<ref>{{cite web
 | title = TSO Extensions (TSO/E), which enhances and extends the capability of TSO, is announced
 | id = ZP81-0796
 | date = November 2, 1981
 | url = https://www.ibm.com/docs/en/announcements/archive/ENUSZP81-0796
 | type = Announcement letter
 | publisher = IBM
 }}
</ref>
|-
| 5665–284
| MVS/Extended Architecture Data Facility Product (DFP) Version 1<ref name="dfp-1-2-general-information">{{cite book
 | title = MVS/Extended Architecture Data Facility Product: General Information
 | date = January 1984
 | edition = Third
 | url = http://bitsavers.org/pdf/ibm/370/MVS_XA/DFP/GC26-4007-2_MVS_XA_DFP_Release_1.2_General_Information_Jan1984.pdf
 | publisher = IBM
 | access-date = 2024-09-19
 }}</ref>
|}

All three 308x systems were withdrawn on August 4, 1987.

=====IBM 3090=====
{{main article|IBM 3090}}

The next series of high-end machines, the '''IBM 3090''', began with models{{efn|IBM used a lower case "m"}} 200 and 400.<ref>{{cite web|url=https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3090.html|title=3090 Processor Complex|website=IBM Archives|date=23 January 2003|publisher=IBM|archive-url=https://web.archive.org/web/20231204192300/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP3090.html|archive-date=2023-12-04|url-status=dead}}</ref> They were announced Feb. 12, 1985, and were configured with two or four [[Central processing unit|CPU]]s respectively. IBM subsequently announced models 120, 150, 180, 300, 500 and 600 with lower, intermediate and higher capacities; the first digit of the model number gives the number of central processors.

Starting with the E<ref>{{cite web|url=https://www.ibm.com/docs/en/announcements/archive/ENUS187-110|title=IBM 3090 Processor Unit Model 120E, IBM 3092 Processor Controller Model 3|type=Announcement letter|publisher=IBM|date=May 19, 1987}}</ref> models, and continuing with the J and S models, IBM offered Enterprise Systems Architecture/370{{sfn|S370-ESA}} (ESA/370), [[Processor Resource/System Manager]] (PR/SM) and a set of backward compatible MVS/Enterprise System Architecture (MVS/ESA) software replacing previous products:

{| class="wikitable"
|-
! Number
! syle="text-align:left" | Name
|-
| 5685–279
| BTAM/SP
|-
| 5668–978
| GAM/SP 2.0
|-
| 5685–001
| MVS/System Product-JES2 Version 3<ref name=SP3>{{cite book
 | title = 5685-001 MVS/System Product-JES2 Version 3 Release 1.0
 | series = IBM Sales Manual
 | date = 8 August 2001
 | url = https://www.ibm.com/common/ssi/cgi-bin/ssialias?infotype=dd&subtype=sm&htmlfid=897/ENUS5685-001#Header_43
 | publisher = IBM
 | archive-url = https://web.archive.org/web/20220411014116/https://www.ibm.com/common/ssi/cgi-bin/ssialias?infotype=dd&subtype=sm&htmlfid=897/ENUS5685-001#Header_43
 | archive-date = 11 April 2022
 | url-status = dead
 }}
</ref>
|-
| 5685–002
| MVS/System Product-JES3 Version 3<ref name=SP3/>
|-
| 5665–293
| TSO Extensions (TSO/E) for MVS/XA
|-
| 5685–285
| TSO/E Version 1 Release 4
|-
| 5685–025
| TSO/E Version 2
|-
| 5665–284
| MVS/XA Data Facility Product (DFP) Version 1<ref name="dfp-1-2-general-information" />
|-
| 5665-XA2
| MVS/XA Data Facility Product (DFP) Version 2.3
|-
| 5665-XA3
| MVS/DFP Version 3.1
|}

IBM's offering of an optional vector facility (VF) extension for the 3090 came at a time when [[Vector processing]]/Array processing suggested names like [[Cray]] and [[Control Data Corporation]] (CDC).<ref>the hyperlink on the words "Vector processing" point to an article that has only 2 mentions of IBM, one of which begins "In 2000, IBM, Toshiba and Sony collaborated."</ref><ref>The "first to market" advantage can be summarized as "In 1972, computer designer Seymour Cray left CDC and formed a new company" as noted in Getting Up to Speed: The Future of Supercomputing, 2005, {{ISBN|0309165512}}, by National Research Council, Division on Engineering and Physical Sciences, Computer Science and Telecommunications Board</ref>

The 200 and 400 were withdrawn on May 5, 1989.

=====IBM 4300=====
{{main article|IBM 4300}}

The first pair of '''IBM 4300''' processors were Mid/Low end systems announced Jan 30, 1979<ref>{{cite web|url=https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4331.html|title=4331 Processor|website=IBM Archives|date=23 January 2003|publisher=IBM|archive-url=https://web.archive.org/web/20231209132724/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4331.html|archive-date=2023-12-09|url-status=dead}}</ref><ref>{{cite web|url=https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4341.html|title=4341 Processor|website=IBM Archives|date=23 January 2003|publisher=IBM|archive-url=https://web.archive.org/web/20230719223403/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4341.html|archive-date=2023-07-19|url-status=dead}}</ref> as "compact (and).. compatible with System/370."

The 4331 was subsequently withdrawn on November 18, 1981, and the 4341 on February 11, 1986.

Other models were the 4321,<ref>{{Cite web|url=https://www.ibm.com/ibm/history/exhibits/dpd50/dpd50_chronology5.html|title=IBM Archives: DPD chronology - page 5| website=[[IBM]] |date=23 January 2003 |archive-url=https://web.archive.org/web/20201021214611/https://www.ibm.com/ibm/history/exhibits/dpd50/dpd50_chronology5.html |archive-date=2020-10-21}}</ref> 4361<ref name="IBM.4361">{{cite web|url=https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4361.html|title=4361 Processor|website=IBM Archives|date=23 January 2003|publisher=IBM|archive-url=https://web.archive.org/web/20230914064000/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4361.html|archive-date=2023-09-14|url-status=dead}}</ref> and 4381.<ref name="IBM.4381">{{cite web|url=https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4381.html|title=4381 Processor|website=IBM Archives|date=23 January 2003|publisher=IBM|archive-url=https://web.archive.org/web/20230719145726/https://www.ibm.com/ibm/history/exhibits/mainframe/mainframe_PP4381.html|archive-date=2023-07-19|url-status=dead}}</ref>

The 4361 has "Programmable Power-Off -- enables the user to turn off the processor under program control";<ref name="IBM.4361"/> "Unit power off" is (also) part of the 4381 feature list.<ref name="IBM.4381"/>

IBM offered many Model Groups and models of the 4300 family,{{efn|One announcement alone featured mention of "Twelve models of the 4381" for just 3 "Model Groups" and also listed 6 other Model Groups}} ranging from the entry level 4331 to the 4381, described as "one of the most powerful and versatile intermediate system processors ever produced by IBM."{{efn|The same IBM web page notes the following date announced/withdrawn dates: Model Groups '''1 & 2''' (Sep 15, 1983 - Feb 11, 1986), Model Group '''3''' (Oct 25, 1984 - Feb 11, 1986), Model Groups '''11, 12, 13 & 14''' (announced Feb 11, 1986), Model Groups '''21, 22, 23 & 24''' (May 19, 1987 - Aug 19, 1992).}}

The 4381 Model Group 3 was dual-CPU.

=====IBM 9370=====
{{main article|IBM 9370}}

This low-end system, announced October 7, 1986,<ref>{{cite web
|url=http://www.ibm.com/common/ssi/cgi-bin/ssialias?subtype=ca&infotype=an&appname=iSource&supplier=897&letternum=ENUS186-178&open&cm_mmc=5733-_-n-_-vrm_newsletter-_-10207_134134&cmibm_em=dm:0:12046832
|title=IBM 9370 INFORMATION SYSTEM OVERVIEW
|date=October 7, 1986|publisher=IBM}}</ref> was "designed to satisfy the computing requirements of IBM customers who value System/370 affinity" and "small enough and quiet enough to operate in an office environment."

IBM also noted its sensitivity to "entry software prices, substantial reductions in support and training requirements, and modest power consumption and maintenance costs."

Furthermore, it stated its awareness of the needs of small-to-medium size businesses to be able to respond, as "computing requirements grow," adding that "the IBM 9370 system can be easily expanded by adding additional features and racks to accommodate..."

This came at a time when [[Digital Equipment Corporation]] (DEC) and its [[VAX]] systems were strong competitors in both hardware and software;<ref>{{cite web
|url=http://inspirehep.net/record/312767/files/ssc-n-691.pdf
|title=Report Of The SSC Computer Planning Committee
|at=chapter 5.4, "SUMMARY OF RELATIVE STRENGTH OF DEC/VMS AND IBM/VM" |date=January 1990}}</ref> the media of the day carried IBM's alleged "VAX Killer" phrase, albeit often skeptically.<ref>{{cite news |newspaper=[[The New York Times]]
  |url=https://www.nytimes.com/1988/01/03/business/the-moment-of-truth-for-big-blue.html
  |title=The Moment of Truth for Big Blue
  |quote=appears to be slaying precious few Vaxes
  |author=David E. Sanger  |date=January 3, 1988}}</ref>