The Gamecube was in the middle of the three. Much faster processor, more RAM, higher FLOPS, etc. Although, looking at it now, the PS2 apparently has 16 pixel pipelines, compared to the Gamecube's 4. I think what happened was that the PS2's GS (graphics card) had more raw power, but the Gamecube had more memory, and was thus able to do more and produce better-looking stuff.