Intel Xeon DP/MP (Paxville) processors
Introduction: October 2005
The Xeon brand refers to many families of Intel's x86 multiprocessing CPUs - for dual-processor (DP) and multi-processor (MP) configuration on a single motherboard targeted at non-consumer markets of server and workstation computers, and also at blade servers and embedded systems. The Xeon brand has been maintained over several generations of x86 and x86-64 processors. Older models added the Xeon moniker to the end of the name of their corresponding desktop processor, but more recent models used the name Xeon on its own. The Xeon CPUs generally have more cache than their desktop counterparts in addition to multiprocessing capabilities. Intel's (non-x86) IA-64 processors are called Itanium, not Xeon.
The Paxville core
The first dual-core CPU branded Xeon, codenamed Paxville DP, product code 80551, was released by Intel on 10 October 2005. Paxville DP had NetBurst architecture, and was a dual-core equivalent of the single-core Irwindale (related to the Pentium D branded "Smithfield") with 4MB of L2 Cache (2MB per core). The only one Paxville DP model released ran at 2.8GHz, featured an 800MT/s front side bus, and was produced using a 90 nm process.
An MP-capable version of Paxville DP, codenamed Paxville MP, product code 80560, was released on 1 November 2005. There were two versions: one with 2MB of L2 Cache (1MB per core), and one with 4MB of L2 (2MB per core). Paxville MP, called the dual-core Xeon 7000-series, was produced using a 90 nm process. Paxville MP clock ranges between 2.67 and 3.0GHz (model numbers 7020-7041), with some models having a 667MT/s FSB, and others having an 800MT/s FSB.
Source: Wikipedia, the free encyclopedia.