Closed loop water cooling is not new, but it certainly is a pretty hot topic now. Some of the first units out there had some interesting issues (like internal corrosion clogging everything up), but once those teething problems were solved the closed loop systems turned out to be pretty effective and easy to install. Initially these units had the performance of a top end air cooler, but with a lot lower noise. The latest generation of liquid cooling systems (LCS) is now further improved and provides performance approaching that of larger, more complex cooling systems. These products will not replace exotic systems like phase change, but they provide a lot of cooling in a fairly decent sized package.
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