AnandTech has a thorough analysis of the CPU performance of both the Xbox 360 and PlayStation 3 consoles, including some choice information from confidential developer sources.  The verdict?  Looks like the CPUs in these two upcoming game consoles are severely hamstringed by a deeply pipelined CPU architecture and poor branch prediction.

Xbox 360’s CPU uses three custom-designed IBM PowerPC cores.  While the PlayStation 3’s “Cell” processor only uses one of these same cores, the rest of the chip is dedicated to an array of SPE units that end up being fairly useless in practice.  Of the two, apparently the developers are finding the Xbox 360’s Xenon CPU the more useful of the two.  The real killer comes on page four of the analysis, when the revelation comes that if either console maker had used an Athlon X2 or Pentium D CPU, they’d have far better performance.

The saving grace in both cases are the rocket-fast GPUs, which will allow the games to look fantastic, and that’s all most gamers will end up caring about once the console is hooked up to their computer monitor or high-def TV.  But it appears that any advances in physics or AI will be delayed for another console generation.

Read More | AnandTech*

*AnandTech has pulled the article sourced here from their website due to concerns that it may have compromised one of their confidential sources.