OVERCLOCKERS ARE ALWAYS LOOKING for something that will help them in their quest for more speed. From high-quality RAM that will run at insane bus speeds to motherboards with every last tweaking option, the list goes on and on. Water-cooling systems, which use water instead of air to cool the processor or other components, are growing in popularity. Such systems typically cool much better than traditional heatsink/fan combos, and run quieter, to boot.
Today we're looking at one such system, Ahanix's Iceberg. The Iceberg is sold as a complete CPU water-cooling kit which includes all necessary hoses and other hardware. Some of its more unusual attributes include its price (only $99, pretty cheap for a water-cooling system) and its ability to install to Socket 370, Socket A or Socket 478 systems with the included hardware. We'll look at the general quality of the kit as well as what's involved with an installation, and we'll also examine the performance under some pretty strenuous conditions. Curious? Read on.
Water cooler primer
If you already know how water coolers work, feel free to skip to the next section. This is for the newbies, or for those who want a refresher.
The processors in mainstream PCs are air-cooled. Typically, air cooling involves strapping a large chunk of metal (a heatsink) to the CPU (metal is a very efficient conductor of heat) and ensuring that said chunk of metal has lots of fins to give it plenty of surface area. The heat generated by the CPU is conducted to the heatsink and the into the air, keeping the CPU cool.
Of course, most modern processors generate so much heat that a heatsink alone isn't enough. Eventually, the heatsink would absorb enough heat that it would be as hot as the processor, at which point it would be doing no good at all. Therefore, a fan is typically mounted on the heatsink blows air over the fins, using that air to absorb heat from the heatsink and cool it off, so it can . . . absorb more heat from the processor. Lather, rinse, repeat ad infinitum (or at least until you shut your system off).
Water-cooling is attractive because water is much more efficient at absorbing heat than airthere's a reason that nearly all modern cars are water-cooled rather than air-cooled. Of course, water-cooling has its own issues. For example, it's no problem to have lots of air hanging out around electronic components, waiting to be directed by a fan to cool a heatsink (in fact, the alternative would be pretty damned difficult). Water, on the other hand, doesn't generally play nice with electronics, so obviously the first order of business is to make sure that the water itself never touches any of the other system components directly. But the water must come close enough to the CPU to cool it properly.
There are other issues, as well. Because air is so abundant, you don't really need to worry about cooling the air after it's been heated by the heatsink. You just use a case fan to suck in . . . more air. With a water cooler however, there is a finite amount of water, and therefore you need to somehow cool that water off, or you'll end up with a repeat of the "heatsink with no fan" scenario outlined above. Finally, you need a place to store the water that isn't either cooling the CPU or being cooled itself, as well as a way to move the water between these areas.
So let's go over these issues one at a time. First, you need something to transfer heat from the CPU to the water, and that component is a waterblock. Basically, it is a metal box with two openings that is mounted to the CPU much like a heatsink. Hoses are attached to the openings, and water flows in one and out the other. While in the waterblock, the water absorbs heat from the CPU (which has been absorbed by the metal of the waterblock) and then carries it away from the waterblock.
Now the hot water coming out of the waterblock needs to be cooled off, so it's directed to the radiator. This device works more or less like the radiator in your car; the hot water pours into a series of small metal tubes with small fins attached to the outside. Many small tubes expose more surface area than one large tube, which cools the water more quickly. Air from a fan is directed through the fins and tubes, which helps the process, much like the fins and fan of an air-cooled heatsink.
Once the water has passed through the radiator and been cooled off, it heads back to the reservoir. The reservoir is basically a watertight tank that holds the majority of the water. The reservoir is also where the pump is located, which is the component that pushes the water through the path outlined abovefrom reservoir to waterblock to radiator and back to reservoir. Hoses connect the various components together and provide a path for the water.