doom 3 and chronicals of riddick, splinter cell are way more advanced, but you know that's why judging a few games to say a console is more powerful then the othere is ridiculous, most developers will tell you that gamecube and ps2 were on equal in power but ps2 was a pain to develope for while gamecube was very simple, and that the xbox was by far the superior console interms of power, the best way to judge a console is by multplatform games, if a console is running multplatform games most of the time better then the othere, its has good power advantage.

Those games may have had more complex shaders, but they also had much lower polygon counts, at 30fps, with less effects, in enclosed spaces. Also, Doom 3 on Xbox had atrocious textures.

Not saying Gamecube was more powerful than Xbox, just that it did pull off some things Xbox was never able to achieve.

Multiplats are not the best way to judge power, because you need games designed from the ground up around a system's hardware to get the most out of it.

Can people start getting banned for the ridiculous mega quote-chains including reposting the same images 10-20x over? It's freaking absurd. If people make have an effort to clean up their quotes then it just doesn't build up like that.

 but To compare two different games, you need poly counts for polys seen and unseen; shadow detail; number of lights; complexities of 'shaders'; complexities of AI; environment size and variety; total texture quality (if one game blows a significant part of its texture budget on a few supoer quality animated textures, for example, the rest of the txtures will take a hit); controller and display lag (a game may make sacrifices in the visuals to get tighter controls); framerates and IQ;...the list goes on and on, and these things aren't measurable just by looking and deciding Game X looks better than Game Y. Even ports don't count as fair tests when issues like budget or developer experience can affect port quality. Or even when a port is tweaked to make a change, like tightening up the controls and sacrificing a little eye candy to achieve that. unless 90% are running  better you can you cant clearly state if that machine is more powerful based on looks.

But with multiplats, the game will inevitably be better suited to one architecture than another, making the comparison slanted.

All the most technically advanced games for their system are exclusives; Conker on Xbox, Rogue Squadron 3 on GC, God of War 2 on PS2, God of War Ascension on PS3, Halo 4 on 360, Jett Rocket on Wii.

thats not true, if the architecture has a notable advantage it will run games better, just like the super nes did against the genesis, just like the xbox did against the ps2/GC and just like the ps4 is doing now with the X1.

I was comparing against Mario Galaxy, not Xbox games.

But different architctures can have different advantages. For instance, a game with heavy use of multitexturing would run better on Gamecube, but a game with normal mapping would run better on Xbox.

the ps2 and xbox was as different as they come, yet xbox used brute force run most ports and run them superior, here is a quote from a developer that developed for all 3 consoles, different architecture  can be a problem if both consoles are close to each other power wise.

"FWIW I don't ever consider any developer who ships anything lazy.
When you're building a cross platform game, there is always an element of lowest common denominator, it's about costs (and I don't just mean financial).
PS2 was often the "lead SKU" at big publishers because of the installed base, Xbox was a version you had to do, in most cases you could write a simple version of your renderer and just drop the assets on Xbox and they would usually run faster. So you'd increase texture quality and call it done.
Usually when you dropped it on gamecube it would run slower and you'd have no memory left, so you downsample to make things fit, figure out how you could use ARAM without crippling performance and ship it.

If you wrote an XBox exclusive with no intention of ever shipping on PC, and you actually spent time optimizing there was a lot of performance to be had, usually most titles were CPU limited because then the polygon indices had to be copied into the GPU ring buffer (which wasn't actually a ring buffer). If your app was pushing a lot of geometry it could literally spend 60% of it's time doing nothing but linear memory copies.
It was possible to place jumps into the ringbuffer, to effectively "call" static GPU buffers, but it was tricky to get right because of the pipeline and the fact you had to patch the return address as a jump into the buffer so you'd have to place fences between calls to the same static buffer. 
If you did this however you could trivially saturate the GPU and produce something much better looking.

On GameCube the biggest issue is it was just had pathetic triangle throughput, the 10M polygons per second (I don't remember the real number) assumes you never clip or light anything.
GameCube was DX7 class hardware for the most part, albeit a more fully featured version than ever shipped in a PC. The GPU just wasn't very fast.
As I said it's real benefit was the memory architecture and I still feel it was over engineered.
On the whole it wasn't a bad machine, but I wouldn't have said it was "more powerful than PS2)"

That dev clearly wasn't very competent at Gamecube development then, as Factor 5 managed 15m polygons a second at launch, and bettered that with 20m two years later.

GC's shader system could do things PS2 could only dream of, and while it was less flexible than Xbox's shader system, the effects it was hardwired for, like EMBM, it could do very, very efficiently. This  is how games like Rogue Squadron 2 and 3, and later on Wii Mario Galaxy 1 & 2 and Jett Rocket, were able to spam certain effects to a level that would choke the Xbox.