One more thing, overclocking can really do damage to your processor, so only do it if you have read a load about it. Overclocking leads to serious heating of the processor, and if it heats up to a certain amount, it can cause PERMANENT damage to the processor. A way to solve this is by finding a good way of cooling it, like a heat-sink. But, even with stuff like that, damage can be done!
Warning: ONLY overclock your processor if you REALLY need to do it for something really URGENT! I can't emphasize the possible damage that could be done to the system!