To be honest,CPUs are clocked at different frequencies(QC Deneb @ 4Ghz,QC Penryn @ 3Ghz),but that is not nearly enough to offset the more than 2x performance difference between 460 and 6870. Amazing what a GPU like Barts can pull.

edit:
ethomaz ,C2 X9650 is a QC as far as I know.