The IBM POWER CPU architecture has been around since the 1990s. Originally, there were two types of POWER based systems. You had Unix boxes which were called “p-Series” and AS/400 machines called “i-series”. They were not compatible and wouldn't interoperate at the OS level. It's a superscalar RISC CPU with a lot in common with the DEC Alpha or SGI MIPS processor. It uses speculative execution, pipelines, and other modern CPU features. Some of the CPUs even had a fairly decent ISA (considering they were RISC).
After 2008, there was a new bevy of POWER servers based on the POWER 7 CPU. These are able to run both OS/400 and AIX. Most POWER systems can also run POWER Linux variants, too.
Remember the PowerPC? Well many of the systems we support come from the RS/6000 line and have PowerPC processors in them. That's what AIX 4.x versions primarily ran on.
PARSEC will support AIX on any platform. The only thing we can't help you with is if you have an ancient version of AIX 3 that runs on the PS/2 x86 platform. We'd love to see it, but we can't support it (not a problem since it was pretty rare and experimental even in he 1990s).