That was a comment on how impressive they are, not a question. ;-)
Sorry.
The CPUs that handle 86% of all credit card transactions for example (in the various mainframes IBM builds). Pretty nice modern architecture still capable of executing 60 year old code.
PowerPC and the z-Architecture (successor to the 360, 370, 390, ...)
Minor nitpick: IBM abandoned PowerPC. Their "low-end" servers are all POWER.
... the ones that only IBM uses in their computers.
You might buy a POWER machine from a boutique manufacturer other than IBM but there were other major players such as Motorola, Apple, then later Nintendo: Nintendo adopted with the GameCube, then Wii, but IBM made custom chips for the XBox360 and the PS3, Nintendo still uses POWER in the Wii U.