Intel Pentium Pro die image, from IntelOn the 1st of November in 1995, Intel launched the Pentium Pro, and had Intel kept its original naming scheme, this would have been the i686. Intel Pentium Pro 200 in socket, image from computerbase.deThe Pentium Pro shared almost nothing with its predecessors beyond its name, manufacturer, and ISA. Internally, the Pentium Pro was a superscalar, out of order, RISC chip with support for speculative execution and register renaming. The Pentium Pro heavily relied upon microcode and that microcode was upgradeable under either the BIOS or operating system control. Additionally, the architecture of the Pentium Pro (P6) would server Intel quite well for more than a decade.