[ Thanks to Jane Walker for this link.
“A p5 system is one that runs on IBM Power architecture with the
new Power5 chip. The Power5 chip, released in 2005, is the fifth
generation of IBM’s line of POWER processors. Power5 brings
simultaneous multithreading capabilities through the new
architectural design of its core.
“But how does Linux play into p5 architecture? Well, you might
want to install Linux on a pSeries server for any of the following