The Intel P6 Microarchitecture: The Pentium Pro

Intel’s P6 microarchitecture, first implemented in the Pentium Pro, was by any reasonable metric a resounding success. Its performance was significantly better than that of the Pentium, and the market rewarded Intel handsomely for it. The microarchitecture also proved extremely scalable, furnishing Intel with a good half-decade of desktop dominance and paving the way for x86 systems to compete with RISC in the workstation and server markets. Table 5-2 summarizes the evolution of the P6 microarchitecture’s features.

Table 5-2. The Evolution of the P6


Pentium Pro Vitals

Pentium II Vitals

Pentium III Vitals

Introduction Date

November 1, 1995

May 7, 1997

February 26, 1999


0.60/0.35 micron

0.35 micron

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