More info is needed realy to get you a more of a yes or no answer realy
Different boards and different cpu's will manage different FSB, my old Q6600 would do 450x8 fairly easy for 3.6ghz on this p35 board and my e8600 does 530x8 just as easy.
If its an amd/i7 chip then im not sure as ive not had any real experience with them, tho guessing as you said p43 im guessing its an intel E or Q series processor.