As CPU speeds rise the heat radiated from them also increases. While the easy solution is to buy a large copper heatsink with a sizeable fan the downside is a loud computer. Try doing this with a dual CPU system and the noise increases. To combat this many are turning to alternative cooling systems, and among the options water cooling is becoming more and more popular.

Directron provides the Koolance PC2-601 water cooling system for $269 without power supply. The CPU-200 comes in at $49.
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