Is it safe to Overclock a Q9400?

[Sinnistter]

So I recently upgraded an old DC7900 with a Q9400 @2.667 MHz. I never replaced the cooling in it, but it looks odd. It's big and black and bulky, the cooler is. Anyway. I was wondering how many more watts it will take to do a slight OC from 2.66 to 3.0 and is it safe to do this small OC on a stock cooler

 

[Robert Cook]

If you keep an eye on the temps and go slowly nothing will blow up. (you might not make it to 3.0 GHz, but you could get close) my question is how do you plan to overclock that chip? does that board support base clock adjustment?