Desktop processor into a Laptop? Vice versa?

HEy I have a dell 8700 with a 3 gig HT p4 processor. I also have a 2.2 gig p4 processor laptop, by Medion ( which I had to get because my dell latitude wont turn on and all it dose is blink the A lock light, I figure its the coolong fan since it dosen't turn on when I hit the power botton, am I right?). Anyways I would like to stick the 3 gig ht processor into my laptop in hopes of getting a faster laptop and saving a bundle. Also I heard something about using processors out of laptops and into desktops is a good thing since they are set for low power settings Im told that they make for good overlocking. ( I was thinking of taking the dell laptops Pent M processor out and over clocking it in the dell 8700, but would prolly need another motherboard or adapter.) Any and all knoledge would be usefull. Also looking for how to overclock my laptop and desktop processors. THANKS!!!