Intel Xeon UP/DP (Dempsey) processors
Introduction: May 2006
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 Dempsey core
On 23 May 2006, Intel released the dual-core CPU (Xeon branded 5000 series) codenamed Dempsey (product code 80555). Released as the Dual-Core Xeon 5000-series, Dempsey was a NetBurst architecture processor produced using a 65 nm process, and was virtually identical to Intel's "Presler" Pentium Extreme Edition, except for the addition of SMP support, which let Dempsey operate in dual-processor systems. Dempsey ranged between 2.50 and 3.73GHz (model numbers 5020-5080). Some models had a 667MT/s FSB, and others have a 1066MT/s FSB. Dempsey had 4MB of L2 Cache (2MB per core). A Medium Voltage model, at 3.2GHz and 1066MT/s FSB (model number 5063), had also been released. Dempsey also introduced a new interface for Xeon processors: Socket J, also known as LGA 771.
Source: Wikipedia, the free encyclopedia.