Nowadays the problem of cooling computer chips is getting more and more complex, since modern processors generate more and more heat, while constantly becoming smaller and smaller. All the high-end Athlon CPUs require heat-sinks that are either made of copper, or equipped with copper inlay, while all the Pentium 4 chips already come with heat-spreaders made of special alloy and utilise huge heat-sinks for better cooling. With high-end CPUs currently dissipating a bit less than 100W of heat it is expected that they will emit 300 and more watts of heat in three or four years time. There are not really many ways to cool-down these hot CPUs and one of the solutions is to use liquid-cooling systems.

There are a number of problems with modern liquid-coolers that are used in personal computers. Basically speaking, I can remember two, or maybe, three types of liquid-coolers that are made for PCs these days. The first type are water-coolers, the second type are the so-called heat-pipes, while the third type is the most complicated and expensive and used in VapoChill solutions. The problem with water-coolers is that they are rather big and may leak, heat-pipes are interesting (read more about them in our Shuttle XPC review) and are even utilized in certain commercial products, but they in fact will not be able to cool-down CPUs of the future since the latter are too hot. There are a number of disadvantages with VapoChill. One of them is the price.

Probably, closed-circuit liquid-coolers that utilise heat-pipe technology have a bit more chances to go into mainstream market since they are rather cheap and are not dangerous in terms of leaking and so on. On the other hand, they may not be enough to cool-down future-generations of CPUs and GPUs and they may become obsolete.

Fortunately, according to this report a new type of conventional heat-pipes was invented in Purdue University by a group of people leaded by Issam Mudawar a professor of mechanical engineering. His research team created a liquid-cooling system that uses a closed loop of two vertical, parallel tubes containing a dielectric liquid. The liquid flows through micro-channels in a metal plate that is touching the chip. As liquid flows through the channels, it is heated by the chip and begins to boil, producing bubbles of vapor. Because the buoyant vapor bubbles are lighter than the liquid, they rise to the top of the tube, where they are cooled by a fan and condensed back into a liquid. The cool liquid then flows into the parallel tube and descends, creating a self-sustaining flow that eventually re-enters the micro-channel plate and starts all over again. The researchers found that the system was 5.7 times better at removing heat than existing miniature pump-less liquid-cooling systems.

The inventors claim that they will continue to implement different versions of solution in order to determine which one works better.