Or buy some lower spec CPUs and overclock them. The C2D 6300 will oc to 3Ghz on air given reasonable RAM and a decent m/b. Avoid the mistake I made using the Asrock dual-vsta m/b as they don't like to oc.
My Gigabyte DS3 C2D 6400 (stock 2.13GHz) is at 2.7GHz and I've only just started messing with it.![]()