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 March 14, 2006, Intel released a dual-core processor codenamed Sossaman and branded as "Xeon" LV (low-voltage). Subsequently, an ULV (ultra-low-voltage) version was released. The "Sossaman" was a low-/ultra-low-power and double-processor capable CPU (like AMD Quad FX), based on the ""Yonah"" processor, for ultradense non-consumer environment (i.e., targeted at the blade-server and embedded markets), and was rated at a thermal design power (TDP) of 31 W (LV: 1.66 GHz, 2 GHz and 2.16 GHz) and 15 W (ULV: 1.66 GHz). As such, it supported most of the same features as earlier Xeons: Virtualization Technology, 667 MT/s front side bus, and dual-core processing, but did not support 64-bit operations, so it could not run 64-bit server software, such as Microsoft Exchange Server 2007, and therefore was limited to 16 GB of memory. A planned successor, codenamed ""Merom MP"" was to be a drop-in upgrade to enable "Sossaman"-based servers to upgrade to 64-bit capability. However, this was abandoned in favour of low-voltage versions of the "Woodcrest LV" processor leaving the "Sossaman" at a dead-end with no upgrade path.