If you're new to the enthusiast game never fear, we've just posted our excellent
Beginners Guides to overclocking. Specifically the processor,
memory, motherboard and videocard.
Overclocking a computer's processor or memory causes it to go faster than
its factory rated speed. A processor rated at 2.4GHz might be overclocked to
2.5GHz or 2.6GHz, while memory rated at 200MHz might be pushed to 220MHz or
higher. The extra speed results in more work being done by the processor and/or
memory in a given time period, increasing the overall computing performance
of the PC.