Xeon
The first Xeon-branded processor was the Pentium II Xeon (code-named "Drake"). It was released in 1998, replacing the Pentium Pro in Intel's server lineup. The Pentium II Xeon was a ""Deschutes"" Pentium II (and shared the same product code: 80523) with a full-speed 512 kB, 1 MB, or 2 MB L2 cache. The L2 cache was implemented with custom 512 kB SRAMs developed by Intel. The number of SRAMs depended on the amount of cache. A 512 kB configuration required one SRAM, a 1 MB configuration: two SRAMs, and a 2 MB configuration: four SRAMs on both sides of the PCB. Each SRAM was a 12.90 mm by 17.23 mm (222.21 mm²) die fabricated in a 0.35 µm four-layer metal CMOS process and packaged in a cavity-down wire-bonded land grid array (LGA). The additional cache required a larger module and thus the Pentium II Xeon used a larger slot, Slot 2. It was supported by the 440GX dual-processor workstation chipset and the 450NX quad- or octo-processor chipset.
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.