Xeon
Introduced in May 2013, Xeon E3-12xx v3 is the first Xeon series based on the Haswell microarchitecture. It uses the new LGA 1150 socket, which was introduced with the desktop Core i5/i7 Haswell processors, incompatible with the LGA 1155 that was used in Xeon E3 and E3 v2. As before, the main difference between the desktop and server versions is added support for ECC memory in the Xeon-branded parts. The main benefit of the new microarchitecture is better power efficiency.
Xeon
On June 26, 2006, Intel released the dual-core CPU (Xeon branded 5100 series) codenamed Woodcrest (product code 80556); it was the first Intel Core microarchitecture processor to be launched on the market. It is a server and workstation version of the Intel Core 2 processor. Intel claims that it provides an 80% boost in performance, while reducing power consumption by 20% relative to the Pentium D.