that's called overclocking. It's common, but I don't recommend it for the same reason I don't recomment running racing fuel in a family car. Yes, it will go faster, but last less.
What, exactly, are you trying to speed up? Boot up time? Web surfing? Games? Need to know exactly where you are slowing down. "I wanna go fast" is not descriptive enough. If it's web surfing, nothing on your pc will speed that up. Get a bigger pipe. If it's boot up time, cut down on your boot up services. If it's gaming, drop a few hundred on a high end graphics card.
Seeing as how you have a laptop, things are limited in what you can do. But we need to know WHAT you want to do first. That machine is a pretty good rig. It's quite more powerful than what I use at work, yet what I use at work is plenty fast for me. It is, however, less than what I have at home, but then again, at home I play a lot of graphics intensive games, so I've invested in some
ram and a nice video card.
It depends where you are experiencing the slow-down.
thanks,
v