POWER9 is a family of superscalar, multithreading, multi-core microprocessors produced by IBM, based on the Power ISA.

[1] The SMT4- and SMT8-cores are similar, in that they consist of a number of so-called slices fed by common schedulers.

A POWER9 core, whether SMT4 or SMT8, has a 12-stage pipeline (five stages shorter than its predecessor, the POWER8), but aims to retain the clock frequency of around 4 GHz.

[1] It will be the first to incorporate elements of the Power ISA v.3.0 that was released in December 2015, including the VSX-3 instructions.

[8] The POWER9 design is made to be modular and used in more processor variants and used for licensing, on a different fabrication process than IBM's.