IBM's midrange computer family, which uses IBM's POWER CPUs. In 2008, IBM merged its System i and System p hardware into the Power Systems brand. It was an easy transition as both System i business computers and System p scientific computers were based on POWER chips, with applications differentiated by operating system. Business applications run under the IBM i operating system, and scientific applications run under AIX (Unix) or Linux.
THE BUSINESS SIDE - AS/400
The business side of Power Systems stems from the AS/400 in 1988 for which thousands of applications have been written over the years. Its unique feature was a relational database that came with the OS/400 operating system, and applications from earlier IBM systems either ran intact or with recompilation (see System/38
AS/400-> iSeries-> i5-> System i-> Power Systems
In 1994, AS/400 models were introduced with the POWER CPUs, and in 2000 IBM renamed the AS/400 the "iSeries." In 2004, the i5 was introduced with the POWER5 CPU and a wide range of models, including systems with 64 CPUs and 2TB of memory. The OS/400 operating system was renamed i5/OS (later IBM i). Subsequent models were branded "System i."
An Early AS/400
The AS/400 was the original hardware line that evolved into Power Systems two decades later. Thousands of applications have been written for it. (Image courtesy of IBM.)
THE SCIENTIFIC SIDE - RS/6000
The computation-intensive side of Power Systems evolved from the RS/6000 workstation in 1990. The RS/6000 was the first to use IBM's POWER CPU, and workstations and servers ran IBM's AIX (Unix) operating system. The RS/6000 originally used IBM's Micro Channel bus but later adopted the industry standard PCI bus.
RS/6000-> pSeries-> p5-> System p-> Power Systems
In 1994, RS/6000 models were introduced with the POWER CPUs, and in 2000 IBM renamed the RS/6000 the "pSeries." In 2004, the p5 was introduced with the POWER5 CPU and a wide range of models, including rack mounted servers up to 64-way systems with 2TB of memory. Subsequent models were branded "System p."
An Early RS/6000
This was one of many RS/6000s, which have been used in scientific and industrial applications. (Image courtesy of IBM.)