Personal computers typically use an air-cooled system to prevent overheating. However, in some situations, proper airflow and cooling fans just don’t keep these high-end components cool enough. Water-cooled computer systems are an effective method of ensuring that PCs placed in extreme heat conditions will stay cool so as to prevent damage to the components. While the price of such a system can be steep, the ability to use a computer in a heat-intensive environment will benefit network administrators who support networks in factories or other extreme-heat locations.

The model used here

For the examples in this article, I used a Koolance PC2-C, which is a standard midsize ATX case outfitted with a water-cooled system.

A business case for water-cooled computer systems
When I first heard about water-cooled computers, my initial thought was that they were designed for the niche market of video gamers who need extra cooling for their overclocked systems. While video gamers are certainly the ones who buy the bulk of these systems, there are business-related situations in which you might need a more robust and reliable cooling system to protect the parts of your computer. One such instance is in the manufacturing plant, where temperatures on the shop floor can regularly top 100 degrees. Such long-term exposure to this type of heat can wreak havoc on sensitive computer components.

You might also consider using water-cooled computer systems in those tiny communications closets in which so many organizations keep their hardware. These rooms hold everything from file servers to WAN gear and are often converted closets that have poor ventilation and little airflow. Their poor design results in high ambient temperatures that can damage the heat-sensitive computer equipment.

Water-cooled systems will allow the owner of a small or midsize business to house a rack or two of water-cooled servers without the prohibitive expense of building or maintaining a large climate-controlled room. Recognizing the business need for such a solution, manufacturers such as Koolance, Inc. are designing water-cooled server cases, including 1U units to be used in smaller IT shops.

The components of a water-cooled system
The Koolance PC2-C water-cooled computer system is comprised of six components: the CPU cooler, the motherboard chipset cooler, the video card cooler, the hard drive cooler, a reservoir, and the top-unit control panel. These components are daisy-chained together using 1/4-inch tubing, with both ends of the chain ultimately connecting to the reservoir. This configuration allows the cool water to be pumped through the system so that it flows over each of the components before reaching the heat exchanger, where it is cooled again. The water flows in this continuous loop and does a very good job of keeping the components in the system at a consistently cool temperature.

One of the misconceptions about water-cooled computer systems is that the physical size of the case is too large. The case of the Koolance PC2-C, shown in Figure A, is 18.1 inches long, 7 inches wide, and 17.9 inches high.

Figure A
The Koolance case dimensions are about the size of an average tower case and should pose no problem for space-starved work areas.

Now that you have an idea of what the outside of the case looks like, it is time to take a peek under the hood and check out the main components of the Koolance PC2-C water-cooled system. For the rest of this section, please refer to Figure B, which shows you what the Koolance PC2-C looks like with all the components of the cooling system installed.

Figure B
Note that the letters A through E designate the various cooling components.

The first component that we will look at is the reservoir, which is labeled with the letter A in Figure B above. This device utilizes a dual pump system that provides redundancy and a push-pull method of moving the cooling liquid through the system. If one of the pumps should fail while the computer is in use, the other pump will take over complete operation of the cooling system until the computer can be gracefully shut down. Because this component is located on the bottom of the case, the danger of leakage damaging your components is minimized. In addition, the easy-to-use refill valve is located on the bottom of the case, which helps protect the computer system in case of a mishap during the refilling process.

Moving on to component B, we see the hard drive cooling unit, which can be used to cool two hard drives simultaneously. To cool a drive, you must first cover the bottom of the drive with a nonconductive paste that will insulate the drive from the actual cooling unit. This compound is then covered by a copper plate, which aids in dissipating the heat from the drive. After installing the copper plate, you mount the drive in the drive bay with the plate facing the hard drive cooling unit. Once the complete system has been installed and powered on, the cooling unit will keep any IDE or SCSI drive safe from overheating.

Component C is the video card cooling unit, which protects the GPU (Graphics Processing Unit) from excessive heat. To use this device to cool the GPU, you will need to install the cooling unit on top of the video processor. This process involves using a heat-dissipating paste to adhere the cooling unit to the GPU.

The letters D and E in the figure above denote the motherboard chipset cooling unit and CPU cooling unit, respectively. Attaching these devices to the chipset and CPU involves a process similar to the one used to attach the video card cooling unit to the GPU.

The final piece of this system is the control panel, which sits on the top of the computer’s case. This component contains the primary heat exchanger, or radiator; power control board; fan cooling module; and an LED display. These parts are powered using the computer’s power supply and provide the cooling for the system. As water flows into this unit through the 1/4-inch tubing, it is cooled and sent back to the reservoir, where it gets pumped through the system again. The LED display on top of the case shows the temperature of the liquid before it is cooled, providing you with accurate temperature readings of the liquid that is being used to cool the computer’s heat-sensitive hardware.

The control unit can be set to run in three modes. When run in mode 1, which is the default setting, the fans run at 45-percent power and the cooling unit keeps the liquid cooled to 95 degrees or less. Should the temperature rise to over 95 degrees, the system will automatically change to mode 2, in which the fans will run at a higher rate and the liquid temperature will rise to 113 degrees. After the system reaches 113 degrees, the cooling system will shift into high gear and move into mode 3, in which the fans will run at 100-percent power and the liquid is cooled up to 122 degrees. If the temperature of the liquid coolant reaches 122 degrees or higher, an audible alarm will sound and the computer will shut down after 30 seconds, before anything can overheat. You can manually set which mode you want to use, but the system will automatically move into the higher modes should the temperature reach the minimum settings for that mode.

CPUs and motherboards for the PC2-C case
The one major drawback to the Koolance case is that it cannot be used with many motherboards or CPUs. Specifically, the PC2-C case will only accept motherboards with a form factor of 12.5 inches by 10.25 inches or 10.25 inches by 10.75 inches. The CPU cooling units cannot be used with SEC cartridges and can only be used by processors such as the Intel Celeron, Pentium 3, Pentium 4, AMD Athlon, and AMD Duron chips.

If you have questions about the compatibility of a motherboard or processor chip, you should contact Koolance, Inc. directly. However, as the popularity of these cooling systems increases, you can be sure that they will be designed to work with a wider variety of components.

The cost barrier
The cost for a liquid-cooled computer system is rather steep when compared to the cost for a traditional air-cooled case. You can expect to pony up about $200 for the Koolance PC2-C. You will also have to purchase a power supply for the case, because Koolance does not include them. According to the folks at Koolance, you can use any standard ATX power supply, because the cooling system only uses up approximately 10 watts of power.

While this type of system is much more expensive than a traditional air-cooled case, if you have a workstation environment exposed to extreme heat conditions, it will pay for itself if it can prolong the life of expensive components. In addition to the ATX case shown in Figure A above, Koolance also has a full tower ATX case that can be used as a server and a 1U unit that can be rack-mounted. You can also purchase the individual cooling-system components and fit them to an existing system.

Condensation and other issues
When I first heard about liquid-cooled computer systems, I immediately began to wonder if they had a problem with condensation. According to Koolance, its cooling system does not use refrigerants. Thus, the radiator’s temperature will always be higher than the ambient temperature inside the case, preventing condensation from forming.

Once I got a look at the way the cooling devices were daisy-chained together in the Koolance system, I questioned whether the liquid would stay cool enough to keep devices near the end of the chain cool. Koolance answers that, because the liquid is being moved through the cooling system so rapidly, there is minimal change in the temperature of the liquid from the first device in the chain to the last device.

As with all mechanical devices, I wondered if the cooling system in the computer would need any additional maintenance. According to Koolance, other than checking the reservoir every six months to ensure that there is enough liquid in the system, the cooling unit needs no additional maintenance.