The power of the Wii

[HappySqurriel]

allthehoneys said:

@Viper1: The Core architecture is more a Pentium than the Pentium 4 ever was. The best reason I can think of that brought Apple to make the switch were the issues regarding leakage power and overall power consumption of IBM's chips. There's a reason we never saw a G5 PowerBook.

It's hard to say how close the Gamecube's CPU was to the performance of the Xbox's, but you certainly can't look at frequencies, cache or ISA alone to make that comparison. The easiest way would be to benchmark them, otherwise there's a lot to account for that can vary in the architecture besides instruction set (such as cache size, cache latency, cache hit rate, functional units, queue sizes, memory size, memory hit rate, data policies, etc) that can affect the price you pay for pipeline stalls or how well you avoid them all together. A good, accurate analysis is a serious undertaking, but I'd recon they'd be close due resemblance to architectures we have seen on the desktop. If I were putting my money on the line, I'd wager the Wii's CPU is much more capable than the Xbox's.

 

Another thing to consider when comparing the XBox and Gamecube's CPU is that (besides cache size) the XBox's CPU was a vanilla celeron whereas the Gekko had 34 (IIRC) additional instructions over its PowerPC counterpart. Typically when you're introducing a new instruction set your goal is to increase the performance in specific tasks, in Nintendo's case with the Gamecube it was to improve in game performance.

Now, I don't know what instructions were added but something as simple as a 'Multiply and add to register' instruction can greatly increase dot-product, matrix-vector, and matrix-matrix calculations which are heavily used in 3D games.