IBM i & AS400 Knowledge Base

The AS400 and IBM i Knowledge Base for the IBM Power Era

Clear answers about AS400, IBM i, iSeries, System i, and modern IBM Power systems ... from legacy terminology to Power11 upgrade planning.

IBM Power S1112 server

AS/400 Is Still How the World Searches for IBM i

AS/400 is the original IBM brand name, but AS400 is still how many IT professionals, executives, and administrators search for IBM i and IBM Power systems. The name changed over time. The business workloads did not disappear.

This site explains the full path from AS/400 to IBM i, from iSeries to IBM Power, and from legacy environments to modern Power11 infrastructure ... without jargon or sales pressure.

1988
AS/400
Application System/400
2000
iSeries
IBM rebrands to iSeries
2006
System i
IBM unified Systems brand
2008
IBM i
Current OS name on Power Systems
2025
Power 11
Latest hardware generation
Glossary

Definitions for AS400, IBM i, RPG, CPW, DB2 for i, and all related terminology.

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IBM Reseller Options

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IBM Power 11

Still Running IBM i Workloads?

Learn how AS/400-era environments map to modern IBM Power systems and when a Power11 upgrade makes sense for your organization.

1
AS400 / IBM i
Your current environment
2
Assessment
CPW, workload, IBM i version
3
IBM Power 11
Right-sized for your workload

Recent Articles

2026-08-14

AS400 End of Life

AS400 end of life depends on which layer you mean: the original hardware brand, the IBM i operating system release, the Power server generation, or the business application running on top of it.

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2026-08-14

AS400 OS

The AS400 OS was originally called OS/400. Today the operating system in that same platform lineage is IBM i, running on IBM Power Systems hardware.

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2026-08-14

AS400 Support

AS400 support can mean IBM i operating system support, IBM Power hardware support, application support, or daily administration support. The right answer depends on the release, the machine model, and the software stack around the workload.

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2026-08-14

IBM pSeries vs iSeries

IBM pSeries and iSeries were different IBM server lines from the same broad Power-era family. pSeries was associated with AIX and UNIX workloads, while iSeries carried the AS400 and IBM i business application lineage.

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2026-08-06

IBM FlashSystem and FlashCore Modules Explained for AS400/IBM i Shops

IBM FlashSystem is external, SAN-attached storage built on IBM's custom FlashCore Module NVMe drives. Here is what an AS400/IBM i shop needs to know before it comes up in a Power hardware conversation.

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2026-07-21

AS400 History Timeline

This AS400 timeline tracks the platform from IBM's June 21, 1988 announcement through the 1995 RISC shift, the iSeries and System i rebrands, IBM i 7.5 and 7.6, and Power 5 through Power 11 milestone dates.

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