Intel Xeon UP/DP (Harpertown) processors
Introduction: November 2007
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 Harpertown core
On 11 November 2007 Intel presented Yorkfield based Xeons - called Harpertown (product code 80574) - to the public. This family came with a dual die quad-core manufactured on a 45 nm process and featuring 1333 to 1600MHz front-side bus, the TDP was rated from 50 to 150 watts depending on the model. All models featured Intel 64 (Intel's x86-64 implementation), the XD bit, and Virtualization Technology, as well as the "Demand Based Switching", except the E5405, which lacked this feature. The supplementary character in front of the model-number represented the thermal rating: an L depicted an TDP of 50 watts, an E depicted 80 watts whereas a X was 120 watts TDP or above. The speed of 3.00GHz came as four models, two models with 80 watts TDP, two other models with 120 watts TDP, with 1333 or 1600MHz front-side bus respectively. The fastest Harpertown was the X5482 whose TDP of 150 watts was higher than those of the Prescott-based Xeon DP but having twice as many cores. This CPU was also sold under the name "Core 2 Extreme QX9775" for use in the Intel SkullTrail system.
Intel 1600MHz front-side bus Xeon processors dropped into the Seaburg chipset whereas several mainboards featuring the Intel 5000/5200-chipset were able to run the processors with 1333MHz front-side bus processors. Seaburg featured support for dual PCIe 2.0 x16 slots and up to 128GB of memory.
Source: Wikipedia, the free encyclopedia.