Computer Project

I am an unrepentant tweaker.  This is my current project machine.

Let me explain.  The white PVC drain pipe is an evaporative cooling tower for the water cooled CPU.  It works just like your local nuclear power plant cooling stack (or swamp cooler).  BTW, this evaporative cooling approach is not original to me.  I saw a couple of posts and pictures on [H]ardOCP awhile back and decided to give it a try.  Here are the interesting bits:

  • IWill KK266 motherboard
  • AMD Athlon 1.33 GHz (266 FSB)
  • 768 MB (3x256) Crucial PC133 SDRAM
  • Leadtek GeForce 2 GTS 32 MB
  • Promise FastTrak66 RAID controller
  • 3 Maxtor DiamondMax Plus hard drives, 27 MB, 30 MB and 40 MB
  • DangerDen Maze4 waterblock
  • SuperMicro 750A server case
  • Enermax 435w power supply
  • The case has been augmented with 2 Panaflo 120mm intake fans (front and side) and 1 Panaflo 92mm exhaust fan (rear).

I don't intend this to be a full technical article on evaporative cooling, but here is the high level stuff.  When water goes through the phase change from liquid to vapor, it absorbs a ton of heat (the latent heat of vaporization).  Some of that heat comes from the air and some from the liquid itself.  In my cooling tower, water is sprayed into the top with a shower head and falls approximately 5'.  As the water droplets fall, some of the liquid on the droplet surface evaporates pulling heat from the droplet.  The cooled water is collected in the reservoir at the bottom (an old picnic cooler) and pumped through the CPU water block, then back to the shower head.  Simple.  Really.

So what does that buy me?  Well, the best overclock I could do with air cooling (a ThermoSonic Thermo Engine) was 1575 MHz.  With the cooling tower I am stable at 1660MHz.  (If you would like to see more performance details, click here.)  Also, I have the soothing sound of falling water and not the hair dryer scream of the 7000 rpm Delta fan.   Besides, it was fun to build.  Here are a few more pics.

This is the shower assembly.  It rests in notches dremeled into the white PVC pipe.

The addition of a fan blowing dry air up the tower increases evaporation.  A 120mm fan fits perfectly on 4" pipe...with a bit of help from some duct tape

The DangerDen water block on the IWill KK266.

This is a screen shot of the SANDRA CPU benchmark. Click the image for larger size benchmarks.

Questions or comments about this site?
Send me an e-mail at