The term "liquid cooled" sounds automotive oriented, doesn't it? Indeed, liquid cooling has been an integral part of the common gasoline engine for the better part of 100 years. Which begs to ask, why is it the preferred method of cooling expensive automobile engines? What's so great about liquid cooling, anyway?
To find out, we must compare air-cooling to liquid cooling. When comparing the effectiveness of cooling methods, there are two properties that matter the most: thermal conductivity and specific heat capacity.
Thermal conductivity is a physical property that describes how well a substance transfers heat. The thermal conductivity of liquid water is about 25 times that of air. Obviously, this gives liquid cooling a huge advantage over air-cooling because liquid cooling allows for a much faster transfer of heat.
Specific heat capacity is the other important physical property, which refers to the amount of energy it takes to heat a substance by one degree. The specific heat capacity of liquid water is about four times that of air, which means it takes four times the amount of energy to heat water than it does to heat air. Once again, water's ability to soak up much more heat energy without increasing its own temperature is a great advantage over air-cooling.
There you have it, the undeniable fact that liquid cooling is more efficient than air-cooling. But that doesn't necessarily mean it's the better choice for PC components, does it?
PC Liquid Cooling
Despite water's incredibly superior heat transferring characteristics, there are some really convincing reasons not to put water in a PC. Foremost of these reasons is liquid coolant's electrical conductivity.
If you were to accidentally spill a cup of water on a gasoline engine while refilling your car's radiator, it's really not a big deal; the water won't harm the engine. On the other hand, if you were to spill a cup of water on your PC's motherboard, that would be a very bad thing. So there is definitely a risk factor associated with water-cooling in the PC world.
Another factor to consider is the maintenance factor. Air-cooling systems are simpler and cheaper to produce and repair compared to their liquid counterparts, and heat sinks require no maintenance aside from getting the dust off of them. On the other hand, liquid cooling systems are definitely more difficult to work with. They definitely require more planning and often require some, albeit minor, maintenance.
Thirdly, PC water-cooling components are much more expensive than their air-cooling counterparts. While a collection of premium air-cooling heat sinks and fans for the CPU, GPU and the motherboard chipset would likely cost under $150, a liquid cooling system for the same components can easily cost upwards of $500.
With all these negatives, it seems like liquid cooling would be a hard sell. But the truth is that the thermal benefits of liquid cooling are so attractive that it's easy to justify dealing with the negatives.
Today's ready-to-install liquid cooling systems are not the mishmash of spare parts the enthusiast had to deal with yesteryear; they are tried and tested platforms. Also, liquid cooling isn't nearly as dangerous as it sounds: sure, there will always be an increased risk when using liquids in your PC-but if you are careful with the materials, that risk is greatly diminished. As far as maintenance, today's coolants need to be replaced quite rarely, maybe once a year. As for price, any equipment that delivers top-tier performance can be justified if it's important to you, be it a Ferrari for your garage or a liquid cooling system for your PC.
So let us continue with the assumption that liquid-cooling appeals to you, or at the very least you'd like to know how it works, what's involved and what the benefits are.