Editing IBM RS64 (section)

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The '''IBM RS64''' is a family of [[microprocessor]]s introduced by [[IBM]] in the mid 1990s, and used in the [[RS/6000]] and [[AS/400]] [[Server (computing)|server]]s.

These microprocessors implement the "Amazon", or "PowerPC-AS", [[instruction set architecture]] (ISA). Amazon is a superset of the [[PowerPC]] [[instruction set]], with the addition of special features not in the PowerPC specification, mainly derived from [[POWER2]]{{cn|date=March 2018}} and the original AS/400 processor, and has been [[64-bit]] from the start. The processors in this family are optimized for commercial workloads ([[integer]] performance, large [[Cache (computing)|caches]], frequent [[Branch (computer science)|branches]]) and do not feature the strong [[floating point]] performance of the processors in the [[IBM Power microprocessors|POWER]] family, its sibling.

The RS64 family was phased out soon after the introduction of the [[POWER4]], which was developed to unite the RS64 and POWER families.