Because neither the PC nor the Mac use either the Pentium or the PowerPC chips anymore?  Mac's have been usign Intel chips for a few years now and the Core 2 Duo (and later processors) have smacked the hell out of every other general purpose CPU out there.   And we didn't even tough graphics for either side.

Wii is more powerful than the Xbox.   Pubishers don't want to spend the money to utlize the Wii's TEV unit to make graphically impressive titles when they can easily port code from the PS2 and slap some waggle in there and ship it.  With the Xbox, graphics were its forte and publishers wanted to spend heavily to brag about their impressive looking games.

If you don't believe me, then you're just accepting ignorance.

@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.

Some GameCube, Wii and Xbox specs:

GameCube CPU: 
485 MHZ (I had this at a lower number, wonder why... Thanks HappySqurriel!)
1.3 GB/s peak bandwidth
64 KB L1 Cache
256 KB L2 Cache

Wii CPU:
729 MHZ
1.9 GB/s peak bandwidth
128 KB L1 Cache
256 KB L2 Cache

Xbox CPU:
733 MHZ
1.0 GB/s peak bandwidth
32 KB L1 Cache
128 KB L2 Cache


GameCube FSB:
162 MHZ

Wii FSB:
243 mhz (?)

Xbox FSB:
133 MHZ


Gamecube Memory:
43 MB total GC of which:
24 MB 1T-SRAM GC (same as on the Wii)

Wii Memory:
64 MB DDR3 400 MHZ? (Twice as fast as the Xbox DDR memory or more)
24 MB 1T-SRAM 10 ns (faster than the Xbox DDR, lower latency)
3 MB Texture Memory
512 MB SD flash memory (can be accessed for buffer purposes(?))

Xbox Memory:
64 MB DDR RAM 200 (?) MHZ 30 ns
8GB HDD


GameCube GPU:
162 MHZ
1 MB texture cache

Wii GPU:
243 MHZ
9.0 gb/s bus

Xbox GPU:
233 MHZ Xbox
6.4 gb/s bus
256KB texture cache (?)

My own personal list. All specifications are not fully confirmed by me against more sources and I will continue to fill in and change the list when i feel like it.

Various places I used to find information:

Wikipedia
http://neonblue2.blogspot.com/2007/12/power-of-wii.html
And other places I cant remember.

There is so much more to it, and I really really think Wii can do much more then Xbox, but it is up to developers and Publishers to use the power.

Edit: Anything more wrong with my list? :D

If I am wrong with something please correct me: The Wii fixed many problems that the gamecube had. The gamecube basically had an architecture than streamed everything at High Bandwidths because of th 1Tsram. I beleive though that in terms of cache the 1Tsram is extremely fast, but when used as main system memory it is outperformed buy the DDR ram in the original xbox. So that is really why the Wii has Gddr3 ram along with the 1tsram. The gamecube also had very little amount of ram compared to the Xbox. The Wii has more ram than the Xbox. The main difference though were how the Gpus performed shaders. Everywhere else they were on par. PC developers were used to the architecture of the Xbox, and could easily develop or port to it. It was basically a PC design with programmable shaders incorporated in the GPU. Now on the gamecube most developers thought it wasn't capable of the same shaders ignoring the TeV units that could produce them. This is basically what Happysquirrel mentioned above, but in easier to understand I guess. Now alot of developers that seem to have gotten use to the gamecube/Wii's architecture seem to be using the TeV more. The Wii basically doubled in raw power and clock speed, and there are probably some other upgrades that nobody found yet.(Nintendo has never released official specs, so we don't know too much about the Wii's hardware). Anyway the Wii is considerably more powerful than the Original Xbox, and we already see that in a few games. We also should see it in more games as time goes on.

man...does it matter?...>_

*checks date*

Phew, I thought I'd travelled back to 2006...

But then wtf? Not this shit again? Well, if you want to argue about this, then fine, go on, I'm not gonna stop you...

 Your Gamecube specs are way off ...

http://en.wikipedia.org/wiki/Gamecube

Wii=original xbox. :O