IBM Power Hardware Center

System i Model History

IBM renamed the iSeries platform System i in 2006, aligning it with the System p, System x, and System z brand family. System i was the last name the AS400 lineage carried before IBM split the OS and hardware brands into IBM i and IBM Power Systems in 2008.

IBM renamed the iSeries platform System i in 2006, folding it into a unified brand family alongside System p (UNIX), System x (x86), and System z (mainframe). System i was a short-lived name, in use for only about two years, but it is a meaningful marker in AS400 platform history: it is the last brand under which the hardware and operating system were sold together as a single named product, before IBM split them apart in 2008.

The System i Rename (2006)

IBM introduced the System i brand in 2006 as part of a company-wide consolidation of its server naming. The change replaced iSeries with System i, matching the parallel System p, System x, and System z lines. The operating system remained i5/OS, continuing the naming introduced with the 2004 iSeries i5 refresh, and application compatibility with earlier iSeries and AS400 software was preserved.

System i Model Line

System i hardware continued to use POWER-family processors, including POWER5+ systems carried over from the late iSeries era and, toward the end of the System i period, early POWER6-based configurations. Model numbers from this era commonly referenced included the System i 515, 525, 550, 570, and 595, spanning entry-level through large enterprise configurations, consistent with the tiered structure IBM had used since the original AS/400 line.

System i and the Power Convergence

System i's two-year run coincided with IBM's broader push to converge its Power-processor-based server lines. By using the same POWER5+ and POWER6 processors across System i (IBM i workloads) and System p (AIX/UNIX workloads), IBM laid the technical groundwork for merging the two hardware brands. This convergence became official in 2008.

From System i to IBM Power Systems

In 2008, IBM retired both the System i and System p brands, merging them into a single hardware family called IBM Power Systems. At the same time, IBM separated the operating system from the hardware brand for good: i5/OS was renamed IBM i. This is the naming structure still in use today, and it is why current IBM i shops describe their hardware as "IBM Power Systems" rather than by any of the earlier AS400, iSeries, or System i names. See IBM Power Systems overview for the current generation.

Frequently Asked Questions

When was the System i brand introduced?
IBM introduced the System i brand in 2006, replacing iSeries as part of a company-wide unification of its server naming into System i, System p, System x, and System z.
What processors did System i hardware use?
System i hardware used POWER-family processors, including POWER5+ systems carried over from the late iSeries era and early POWER6-based configurations toward the end of the System i period.
How long was the System i brand in use?
System i was in use for about two years, from 2006 to 2008, when IBM merged it with System p into the current IBM Power Systems brand and renamed the operating system IBM i.
What replaced System i?
In 2008, IBM replaced System i with two separate brands: IBM Power Systems for the hardware, and IBM i for the operating system, which was previously called i5/OS.