Part I of this series covered Microsoft"s vision for dynamic content creation in the next generation of console games. The XBox 360"s procedural synthesis techniques were explained, and a general overview of the multicore PowerPC CPU that powers the new console was given. In the present article, we"ll zoom in for a closer look at this CPU, codenamed Xenon. We"ll cover the design of its individual parts, and we"ll talk about how each part fits with the vision outlined in Part I.
Xenon"s design philosophy
The Xenon"s triple-core design shares some DNA with the Playstation 3"s Cell processor, so it"s not surprising that it also embodies many of the same assumptions about the best way to wring performance out of the sorts of extremely large transistor counts that Moore"s Curves have given the latest generation of integrated circuits. Like the Cell processor that will power the Playstation 3, the Xenon carries on the "RISC"-style tradition of trading programmer/compiler effort for hardware. In a nutshell, software writers who develop for Xenon must take on more of the burden of optimizing their code by making it explicitly parallel, and in return they get more execution hardware to play with.