Geoff, "the Gas man" Gasior over at the Tech Report has been monkeying around down in the Damage Labs again. This time around, he's taken a P4 520, which runs at 2.8GHz stock, & pushed it all the way to 3.57GHz! Not only that, he did it on nothing but stock aircooling.

"Since the Pentium 4 500 line stretches from 2.8 to 3.6GHz, lower speed grades may have considerable overclocking headroom just waiting to be exploited. How much headroom? I got an extra 770MHz out of my Pentium 4 520 2.8GHz, which is quite comfortable running at 3.57GHz with stock air cooling—not bad for a chip that costs less than $160."