While the words CPU and microprocessor are used interchangeably, in the world of personal computers (PC), a microprocessor is actually a silicon chip that contains a CPU. At the heart of all personal computers sits a microprocessor that controls the logic of almost all digital devices, from clock radios to fuel-injection systems for automobiles. The three basic characteristics that differentiate microprocessors are the following:

• Instruction set: The set of instructions that the microprocessor can execute.
• Bandwidth: The number of bits processed in a single instruction.
• Clock speed: Given in megahertz (MHz), the clock speed determines how many instructions per second the processor can execute.

The higher the value, the more powerful the CPU. For example, a 32-bit microprocessor that runs at 50MHz is more powerful than a 16-bit microprocessor that runs at 25MHz.

If you think overclocking sounds like an ominous term, you have the right idea. Basically overclocking means to run a microprocessor faster than the clock speed for which it has been tested and approved. Overclocking is a popular technique for getting a little performance boost from your system, without purchasing any additional hardware. Because of the performance boost overclocking, is very popular among hardcore 3D gamers.

The most common methods of overclocking your CPU is to either raise the multiplier or raise the FSB (frontside bus) — while not the only options they are the most common. To understand overclocking, you have to understand the basics of CPU speeds. The speed of a CPU is measured in Megahertz (MHz) or Gigahertz (GHz). This represents the number of clock cycles that can be performed per second. The more clock cycles your CPU can do, the faster it processes information.

Example:
(1) Pentium III 450MHz
The CPU runs at 450 million clock cycles per second. The CPU runs at at a speed of 450 megahertz. Using our processor speed equation we have: 100MHz (frontside bus) x 4.5 (multiplier) = 450MHz (processor speed)

The frontside bus connects the CPU to the main memory on the motherboard — basically, it's the conduit used by your entire system to communicate with your CPU. One caution with raising the FBS is that is can affect other system components. When you change the multiplier on a CPU, it will change only the CPU speed. If you change the FSB you are changing the speed at which all components of your system communicate with the CPU.

Overclocking comes with many risks, such as overheating, so you should become familiar with all the pros and cons before you attempt it. Additionally, overclocking isn't supported by the major chip manufacturers which means overclocking your CPU will void your warranty. Overclocking can also decrease the lifespan of the CPU, cause failure in critical components and may even result in some data corruption. You may also notice an increase in unexplainable crashes and freezes.

You can find many complete step-by-step guides available online that detail the actual process of overclocking. If you've decided to take the plunge and overclock your CPU, we recommend you don't start with your only usable system (try using outdated and cheap hardware to practice with) and be sure to find a knowledgeable source and read some of the overclocking information and Web pages listed below in the links section to get you started in the right direction.