Cubase SX 3 / WinXP user ready to get current

old DAW died, scrambling to start ordering parts for a new one, need a page of systems and components that have been tested (either by Steinberg or machines that Cubase7 fans use that seem to work well ) - looking for adequately powered and quiet.

Also, can Cubase7 use as many cores/threads as I can provide with processor?

Thx.