The Unabridged Pentium 4 IA32 Processor Genealogy

Introduction

The Xeon based on the Pentium® II processor was the first Xeon. Xeon processors target the workstation and server market and support either two (in a Xeon DP product), or four (in a Xeon MP product) processors on the FSB. With the following exceptions, the Pentium® II Xeon was identical to the Pentium® II:

• While all models of the Pentium® II had a 512KB L2 Cache, the Pentium® II Xeon was available with a 512KB, 1MB, or 2MB L2 Cache.

• While the Pentium® II's BSB operated at 50% of the processor's core speed, the Xeon's BSB operates at 100% of the core speed.

• The Xeon implemented a Processor Information ROM, a scratch EEPROM and a thermal diode that could all be read via the serial SM Bus.

The Pentium® II implemented two pins (BR[1:0]#) ...