Editing IBM RS64 (section)

==Cobra and Muskie==

In 1995, IBM released the '''Cobra''', or '''A10''' processor, the first full implementation of PowerPC AS, for the IBM [[AS/400]] systems. It was a single-chip processor running at 50-77&nbsp;MHz. It was designed with a semi-custom methodology, as a consequence of time-to-market constraints. The die contains 4.7 million [[transistor]]s and measures 14.6&nbsp;mm by 14.6&nbsp;mm (213&nbsp;mm<sup>2</sup>). It was fabricated by IBM in their CMOS 5L process, a 0.5&nbsp;[[μm]], four-layer-metal CMOS process. It used a 3.0 V power supply and dissipated 17.7 W maximum, 13.4 W minimum at 77&nbsp;MHz. It was packaged in a 625-contact [[ceramic ball grid array]] (CBGA) that measured 32&nbsp;mm by 32&nbsp;mm.

Cobra was preceded by a simplified implementation known as '''Cobra-Lite''' in 1994, which was used in the first [[IBM Advanced/36]] systems.<ref name="inside-as400" /> It lacked 17 instructions from the full PowerPC AS ISA which were not needed for the Advanced/36.

In 1996, IBM released the high-end, 4-way [[Symmetric multiprocessing|SMP]], multi-chip version called '''Muskie''', '''A25''' or '''A30''' in AS/400 systems. It ran at 125-154&nbsp;MHz. It was manufactured on a [[BiCMOS]] fabrication process.

These processors were only used in AS/400 and Advanced/36 machines.