What they could use is a multiple core graphics chip. If you had 4 graphics cores, you could give each one a quarter of the screen output. You would instantly quadrupal the capabilities of the machine. Remember 3DFX Voodoo 2 was able to work 2 cards at a time for high performance. One would render the current frame, while the 2nd would render the next frame...SLI I beleive it was called. I wouldn't be surprised if this is where MS pulls a dual core, because graphics power is really where consoles are growing on needs, not the CPU power.