Advantages of overclocking
* You can, in many cases, purchase a slower component for a cheaper price and overclock it to the speed of a more expensive component.
* Faster performance in games and applications at no additional expense. This can lead to higher performance in some games, especially the very popular multiplayer modes in first person shooters.
* General computing tasks can be made faster, eg. booting up, moving files, and installing an operating system.
* Small overclocking of a component can help realize the full potential of another component to a greater percentage than the limiting hardware is overclocked. For instance, many motherboards with AMD Athlon 64 processors limit the speed of four units of RAM to 333 MHz. However, the memory speed is computed by dividing the processor speed (which is a base number times a multiplier, for instance 1.8 GHz is most likely 9x200 MHz) by a fixed integer such that, at stock speeds, the RAM would run at a clock rate near 333 MHz. Manipulating elements of how the processor speed is set (usually lowering the multiplier), one can often overclock the processor a small amount, around 100-200 MHz (less than 10), and gain a RAM clock rate of 400 MHz (20% increase), realizing the full potential of the RAM.
* Overclocking can be an engaging hobby in itself and supports several dedicated online communities such as those listed below.
Disadvantages of overclocking
* Increasing the clock speed and/or voltage of a component can shorten its lifespan and possibly damage it.
* Increasing the clock speed of a component usually increases its power consumption or electrical "workload", which causes a rise in temperature. If the temperature rises too high the component can fail.
* More common than hardware damage is crashing, although it is often possible to reboot the system after leaving it to cool for a short time. Although the hardware is not permanently damaged, this is inconvenient and could cause data loss. In rare, extreme cases entire filesystem failure may occur, causing the loss of all data.
* Not every component of a computer is overclockable; for example, hard drive platters usually cannot be made to spin any faster. Where hard drive read/write rate is the bottleneck, as it often is, overclocking brings little or no speed advantage.
* Personal computers are mostly used for tasks which do not push the hardware, or where the speed of a task is restricted by bottlenecks outside of the local machine. For example, web browsing does not require a very fast computer, and the limiting factor will almost certainly be the speed of the internet connection. Other general office tasks such as word processing and sending email are more dependent on the efficiency of the user than on the speed of the hardware. In these situations any speed increases through overclocking are unlikely to be noticeable.
* It is generally accepted that, even for computationally-heavy tasks, speed increases of less than ten percent are difficult to discern. For example, when playing video games, most people would fail to notice an increase from 60 to 66 frame/s without the aid of an on-screen frame counter. Generally, gains of a few percent are sought for prestige rather than real-world computational benefit.
* Products sold specifically for overclocking are sometimes just decoration. Although this is not a bad thing in itself, buyers should be aware of the marketing hype surrounding some products. Examples include heat spreaders and sinks designed for chips which do not generate problematic amounts of heat.
* Powerful fans usually create a lot of noise, which may make them unsuitable for desktop use. Quiet overclocking can be difficult, although specialised products are available. Generally it is possible to make a component quieter or faster, but both are considerable challenges. Some people do not mind the extra noise, and it is common for overclockers to have computers much louder than stock machines. In HTPC situations noise is critical, so overclocking is not advisable. Quieter options for overclockers include liquid and phase-change cooling.
* Overclocking will not necessarily save money. Non-trivial speed increases often require premium cooling equipment, and once the hobby bites it can become an expensive pastime. Most people who consider themselves overclockers spend significantly more on computer equipment than the average person.
* Overclocking usually results in the voiding of the manufacturer's warranty.
