Hardware Hacking Projects for Geeks

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Chapter 4, How to Build a PC Water-Cooling System

Next, locate the CPU Clock Multiplier. Increase this multiplier a small

amount, save the BIOS changes, and reboot the system. Switch on the

water-cooling system and boot the system to Windows. Run one of the CPU

monitoring utilities as well and look at the temperature. If everything is sta-

ble, reboot back to the BIOS setup and increase the CPU Clock Multiplier

a little. Repeat this procedure until the PC is no longer stable. At this point,

reduce the CPU Clock Multiplier a little and re-verify system stability.

You should now have an overclocked PC with a water-cooled processor!

Project Demo

Figure 4-26 shows a 650 MHz Intel PII system that has been over-

clocked to 1 GHz. Note the 1,000 MHz at the top of the screen.

Check the CPU temperature and core voltages from the BIOS. You

should see that the cooling system keeps the temperature in the

seventies to low eighties.

Extensions

What you’ve seen so far is a very basic water-cooling setup, which

can be somewhat clumsy for everyday use because it uses an open

pan of water. In this section I describe how to add a small radiator

and water reservoir, another method to cool the water. Space doesn’t permit

a complete step-by-step set of instructions, so I’ll just give you some loose

guidelines to follow if you’re interested in pursuing the radiator on your

own.

Add a radiator and a closed flow system

Purchase a standard automobile oil radiator from an auto parts store. These

radiators are rather small and lightweight. Get a few different hose diameter

adapters so that the input and output tubes from the radiator match the

hose to the CPU cooler and water reservoir.

Because the system will become a closed circulation system, you need a

way to prevent air bubbles from forming inside it. Air bubbles will disrupt

operation and need to be removed. A reservoir will allow you to add water

and bleed the system of air. A 4-inch-square underground plastic electrical

box from a local hardware store should work well. You will need to drill

two holes in the top and add brass hose barbs for connection to the water

system. You can see a schematic diagram of this in Figure 4-27.

Figure 4-26: Overclocking results

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Part I: Basic Hacks, Tools, and Techniques

If you do decide to add a radiator, note what type of metal it is made of. If

the water block and the radiator are made of different materials, such as

aluminum and copper, you have the basic elements of a battery. Over time,

these two dissimilar metals will react through the water and begin to break

down. There are several things you can do to prevent this. One, use de-ion-

ized water. Two, add a small amount of Water Wetter from Red Line Oil Inc

(http://www.redlineoil.com/), which will slow and prevent any corrosion.

As mentioned previously, it is important to ensure that the water-cooling

block be in contact with as much of the CPU as possible. If you want to get

a good thermal connection, you may want to use a small amount of ther-

mal grease. This material is often called heat-sink grease and is available at

Radio Shack.

Water flow through the system will be limited by the diameter of the tubing.

Once you have built one or two water blocks, you may want to experiment

with designs that use larger-diameter hoses. You may even want to add

quick disconnect couplings to allow easy assembly and disassembly of the

hoses from the PC case.

Cooling other components

The system CPU is not the only component that can be overclocked for

increased performance. The chip on the graphics card can also be run faster

than normal with a water-cooling system. You will need to change the size

and possibly the shape of your water block to fit onto the other chips, but

this is easily done.

Water block

Water pump

Hose

Radiator

Optional

fan

Water reservoir

Figure 4-27: Cooling system with radiator and reservoir

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