IBM System/390

IBM System/390
	Inside the IBM S/390 Parallel Enterprise Server Generation 4
Manufacturer	International Business Machines Corporation (IBM)
Type	mainframe (S/360-compatible)
Release date	September 5, 1990
Discontinued	December 31, 2004
Operating system	MVS/ESA, OS/390, VSE/ESA and VM/ESA
Memory	ES/9000: up to 2 GB main + 8 GB expanded ; 9672: up to 32 GB main (2 GB flat)
Predecessor	IBM 3090, 4300 and 9370
Successor	IBM Z
Website	Official website IBM Archives; "System/390 Announcement". IBM Archives. IBM. 23 January 2003. Retrieved 2017-01-29.

The IBM System/390 is a discontinued mainframe product family implementing ESA/390, the fifth generation of the System/360 instruction set architecture. The first computers to use the ESA/390 were the Enterprise System/9000 (ES/9000) family, which were introduced in 1990. These were followed by the 9672, Multiprise, and Integrated Server families of System/390 in 1994–1999, using CMOS microprocessors. The ESA/390 succeeded ESA/370, used in the Enhanced 3090 and 4381 "E" models, and the System/370 architecture last used in the IBM 9370 low-end mainframe. ESA/390 was succeeded by the 64-bit z/Architecture in 2000.

^ "Family 9672+07 IBM S/390 Generation 6 Servers: Engines for e-business". IBM. 22 September 2010.

[1] "Family 9672+07 IBM S/390 Generation 6 Servers: Engines for e-business". IBM. 22 September 2010.

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