Overclocking (higher clock rate = more clock cycles per second) is a method for increasing performance of standard computer components, such as motherboard bus speed, CPU speed, or both, to their potential speeds beyond the manufacturer’s rated specifications. It is also called pushing or speed margining.
Efforts are usually focused on processors, video cards, motherboard chipsets, and Random Access Memory (RAM). The CPU multiplier and the motherboard’s front side bus (FSB) speed [or QPI (Quick Path Interconnect), also known as Baseclock (BCLK)] is manipulated until a maximum stable operating frequency is reached.
The performance gains that can be obtained through overclocking are substantial, but a lot of consideration must be done before taking the steps to overclocking a system. It is important to know the risks involved, the steps that must be done to obtain the results and a clear understanding that results will very greatly. The primary benefit of overclocking is additional computer performance without the increased cost. [About.com]
The biggest obstacle to overclocking the computer system is heat. A large amount of heat is already produced by today’s high-speed computer systems, and overclocking a computer system just compounds these problems. Because of this, high performance cooling solutions are needed, which includes CPU heatsinks and fans, heat spreaders on memory, fans on video cards and case fans. Large copper heatsinks (good conducting metals) and a great number of case fans (for proper airflow) are recommended.
Overclocking is a risky process and doing this will void your warranty and may lower the lifespan of the selected hardware, so do your research very well about the components and the steps involved to be sure of what you are doing.
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