Editing IBM System/370 (section)

=====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.