Xenon is a CPU that is used in the Xbox 360 game console. The processor, internally codenamed "Waternoose" by IBM[1] and "XCPU" by Microsoft, is based on IBM's PowerPC instruction set architecture, consisting of three independent processor cores on a single die. These cores are slightly modified versions of the PPE in the Cell processor which was designed specifically for the PlayStation 3.[2][3] Each core has two symmetric hardware threads (SMT), for a total of six hardware threads available to games. Each individual core also includes 32 KiB of L1 instruction cache and 32 KiB of L1 data cache.
The processors are labelled "XCPU" on the packaging and are manufactured by Chartered. Chartered reduced the fabrication process in 2007 to 65 nm, thus reducing manufacturing costs for Microsoft.
The name "Xenon" was repurposed from the code name for the Xbox 360 in early development.
IP ownership strategy with the chips could dramatically cut Microsoft's costs on the original Xbox. Microsoft had lost an estimated $3.7 billion over four years, or roughly a whopping $168 per box.
