Damn, Luca...I'm impressed. You seem to know what's what in that stuff.
Could you just imagine some of the wild-ass stuff out there if people could build their own Macs with mail order catalog/web wholesaler parts?
Guys would be cramming 4 G5 processors into a big box, with a graphics card the size of newspaper wedged in, 4 FireWire 800 ports, three onboard iSight cameras (face, window, crotch), 16GB of RAM, etc.
...and STILL bitching about frame rates or Photoshop performance.