New Xbox 360 CPU details, and fresh Cell info
IBM has been posting papers from the recent Fall Processor Forum 2005, and the papers include plenty of info on the hardware inside of two of the three next-gen consoles: the Xbox 360's Xenon CPU and the Playstation 3's Cell.
The paper on Xenon by Jeffery Brown, "Application-customized CPU design: The Microsoft Xbox 360 CPU story," was the one that I was most interested in. There was a lot of speculation on the nature of the processor core design that IBM used in the Xenon—was it from the POWER4/970 lineage, or was it a tweaked version of the Cell's PowerPC Processing Element (PPE)?
All signs and available information pointed pretty clearly to it being the latter, but still there were holdouts who insisted that the Xenon's three cores were something else entirely. The new paper puts to rest any doubts with an architectural diagram and some details on the new core. The only thing they didn't include was a pipeline diagram and a stage count, but that doesn't really matter because the Cell docs cited in the Xenon paper's footnotes include such (previously known) information.
