The first POWER processor was designed at the end of the 1980’s and made its appearance in the RS6000 and AS/400 servers. The RS/6000 was running AIX, IBM´s Unix version, and the AS/400 was designed for OS/400 (now called IBM i). These servers were designed to allow a tight integration of database and application running together on one server, a concept introduced long before the appliance concept become common in the market. Later, those servers were to merge into a single family – the POWER Servers.

Source : IBM