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Liquid Cooling

Modern CPUs generate twice as much heat as CPUs did five years ago. This is even truer for the GPUs. For example, a powerful dual-processor graphics card can generate as much as 380 watts of heat. Many contemporary machines use multiple processors and graphics cards, making the efficient cooling of these components a priority. Removing such vast amounts of heat in a space-constrained environment such as a computer chassis is traditionally done at the cost of an uncomfortably high noise level from the fan. Liquid cooling minimizes the noise level required. Liquid cooling is also the best solution for rapid heat removal due to the high thermal output of the GPUs and CPUs in gaming systems and high performance computers respectively. A water block normally offers a lower profile cooling solution and it allows double computational power in the same cubic footprint. The liquid cooling system dramatically lowers the operational temperatures and increases the ability to overclock CPUs to higher levels without damage.

Liquid cooling takes advantage of a basic principle of thermodynamics — that heat moves from warmer objects to cooler objects. As the cooler object gets warmer, the warmer object gets cooler. The sole purpose is to transfer heat (energy) away from critical computer components quickly and effectively. The heat is usually transferred to the surrounding environment by dissipating the heat through the heat sink and radiators. Water has a high level of thermal conductivity, meaning it absorbs heat better than air. Liquid cooling works by running water through the channels in the water block attached to each of the components that require cooling, transferring heat from each part to a radiator that dissipates the heat and keeps the water cool — similar to a car's radiator. This lets the processor, graphics card, and other hardware cool down much more effectively.

Liquid cooling allows the transfer of more heat from the components being cooled than air, making liquid cooling perfect for overclocking and high-performance computer applications. In comparison to air cooling, liquid cooling is not influenced by the ambient temperature, making it a better choice in environments with a high ambient heat. Also, liquid cooling has a relatively low noise level because it uses much quieter and smaller fans than those used in active cooling.

The major drawbacks of liquid cooling are complexity and cost. Also, liquid cooling can be messy and cause damage when a failure in pipe connections occurs. Liquid cooling also needs a good deal of power to operate the pump. Despite some of these drawbacks, liquid cooling is still popular with gamers because of its efficiency and effectiveness.

In a liquid cooled system, each component that requires cooling has a cooling plate (heat sink) attached to it. This heat sink, usually made of copper or aluminum, is a hollow plate with an input and an output hose through which the coolant will flow. The circulating pump will circulate the coolant from the radiator to the cooling plates, then to the tank and back to the radiator, where the heat is dissipated.

Here are more details about each component:

Radiator: The radiator moves the absorbed heat into the surrounding environment by using a cooling fan to effectively cool the liquid. The bigger the radiator, the more effective it becomes, which results in lower liquid temperature and a lower component temperature.

Water block: The water block (or heat sink) absorbs the heat from the microprocessor. It contains microfins that are used to boost the surface area for more optimal heat transfer. As the liquid flows through the water block, it absorbs the heat. If you have a more efficient water block, your overall component temperature will decrease.

Water pump: The water pump provides the circulation of the liquid in the cooling loop from the hot side to the cold side. This allows for effective heat transfer throughout the entire loop. Without a good water pump, the liquid would stagnate in the loop and heat transfer would not occur.

Reservoir: The reservoir unit allows for easier removal of air after the initial liquid cooling installation and serves as an expansion area for the coolant during temperature fluctuations.

Liquid cooling system. Photo used under CC-BY-NC-ND license from Terror Noize.

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