Without much fuss, Intel started shipping new Xeon processors built on 0.13micron Prestonia core. Prestonia core is a server analogue to Northwood and differs from the previously used Foster core by the following features:

• Prestonia is made with 0.13micron manufacturing technology while the old Foster core was made with 0.18micron process.
• Like Northwood, Prestonia features 512KB L2 cache, while Foster had 256KB L2 cache.
• The CPUs on Prestonia core support HyperThreading technology, which allows executing multiple calculation threads on a single CPU. Older processors on Foster core did not support HyperThreading technology.

The new Xeon processors based on the new core support 1.8GHz, 2GHz and 2.2GHz core frequency and are officially called Xeon 1.8GHz, Xeon 2.0A GHA and Xeon 2.2GHz (the CPU with 1.8GHz core clock doesn’t have an “A” suffix, because there are no Foster based Xeon processors supporting this core frequency). The new Xeon (Prestonia) processors in 1,000-unit quantities cost: $251, $417 and $615 for 1.8GHz, 2.0GHz and 2.2GHz respectively.
We should point out that the announced Xeon CPUs are positioned by Intel as solutions for workstations, but in no way for servers. For the server market Intel is planning Xeon MP processors scheduled for March 2002. Although Xeon MP will be based on Foster MP core with 256KB L2 cache produced with 0.18micron technology, these CPUs will also have a 512KB L3 cache unlike their brothers. The L3 cache will be 512KB, 1MB or 2MB big. The first Xeon MP CPUs will work at 1.4GHz, 1.5GHz and 1.6GHz.
Since the freshly launched Xeon CPUs on Prestonia core are not targeted for the server market, Intel doesn’t recommend using HyperThreading technology in systems built with them, as this technology is intended for server needs in the first place. Nevertheless, Socket603 mainboards supporting Prestonia have an option in the BIOS enabling this technology, and Windows XP OS supports it as well. When HyperThreading in enabled, multi-threaded applications (optimized for multiprocessor systems) get accelerated by almost 10%-20%, and Windows XP recognize each of Xeon (Prestonia) CPUs as "a pair of logical CPUs".
Xeon (Prestonia) processors are supported by i860 chipset and can work in dual-processor configurations.
NEC and HP will start shipping workstations built on new Xeon CPUs in the nearest future.