Overclocking is the word used to describe the action of forcing a computer component to run at a high clock rate than it was originally intended to by the manufacturer. Overclocking is mainly performed by PC enthusiasts who either buy low end components and overclock them to the speeds of more expensive hardware, or buy high end components and attempt to achieve performance levels that manufacturer "stock" speed products are not capable of reaching.

Overclocking currently focuses on CPUs, graphics cards (GPUs), motherboard chipsets and RAM. The CPU, motherboard and RAM are generally overclocked using the system’s BIOS (although windows applications do exist they are considered to be not as powerful as BIOS overclocking) while graphics cards are overclocked using Windows based applications.