How do you overclock a hp pavillion cpu?

[CacoFFF]

And i was about to recommend you a pinmod...

Your current BUS speed is 266.
The FSB is 4 times the BUS speed, 1066 in your case.
The processor has a multiplier, locked in most cpu's, unlocked in Intel Extreme and AMD Black Edition and FX.
The final processor speed is BUS x Multiplier, by doing simple math: 2.400 / 266 = 9, we get that you have x9 multiplier.ç

There are two ways of overclocking, one is increasing multiplier (safer and easier) other is raising fsb (affects the whole socket and RAM).

Does your BIOS allow you to change the BUS speed?