PC in a fridge – David Curtis
Since 1998, when I bought my first computer (that wouldn’t run a MHz over stock speed), I have been using water cooling of one sort or another to help with overclocking. After having run with a water block and an external tank inside my fridge, a “bong” type cooler, standard radiator cooling, water cooled peltier systems and just using a 50 litre container full of water with no radiator or fans, I figured I could do better if I could get the whole computer inside the fridge.
As I had a spare A7V266-C, PSU, RAM and a XP1700+ not being used, I decided it was time to try. I found a used hotel room type fridge that looked just big enough for the water tank, mainboard and other necessary stuff to make the computer work. Several days of food/beers/coffees and placing various components in a number of different positions later, it was sorted.
First I made up a water tank of 3mm clear acrylic sheet that fitted in the lower part of the fridge:
Then from the same acrylic sheet, I cut a piece to mount onto the mainboard; this also formed the cover of the water tank. Just under the CPU socket, I bolted a slim 60mm fan to blow cool air directly upwards to cool the back of the socket. In the front corner of this, I used a PCI slot fan to blow the warm air from around the mainboard back into the water tank to cool down again.
As fridge doors were not really designed for computer parts, it was trashed, replaced with a stainless steel frame and clamped in place to form an airtight seal.
To fill the hole in the middle, I bent up a piece of 5mm clear acrylic sheet, as you can see in the picture. The top part of this is used to house the hard drive, floppy drive PSU, front panel USB/sound sockets, LED’s and power/reset switches. They are outside the cold part of the fridge, but still inside, if you see what I mean. In the base of this, I cut a long slot to run all the cables down to the mainboard. All the cables were run through a separate panel and sealed up.
In the centre of it, a square was cut out and all the I/O cables were run through this small panel, sealed up and the panels screwed back into place. The top reading on the thermometer shows the coolant as it returns from the water block into the tank, and the lower reading is the temperature inside the fridge in front of the mainboard.
The cables were sealed to keep the air from getting into the fridge. Last, a very cheap fish tank thermometer to the right of the digital one also shows the temps around the mainboard – not really needed, but useful when the batteries in the digital ones expire.
To help keep the inside of the fridge cool, I mounted a small desk fan on the back of the fridge to blow air over the compressor, as it gets very hot when the fridge is running. It made a huge difference, as the fridge has to work much harder than normal for some strange reason 🙂
Assembling the bits was no different as any other computer with the exception of not having very much space at all around the PSU/drives to connect things up. I wired it so that the pump switch also turns off/on the power to the PSU, so there is no way of starting the computer without switching the pump on first. The water return lines are located right in the front of the fridge and are visible at a glance, so if the pump does stop working, you’ll see it immediately.
I fitted the frame on to where the door used to be, clamped it shut, turned the fridge on and left it running for a day to make sure there was no condensation forming inside anywhere. No sign, so I turned the pump on and fired it up. It went straight into the BIOS:
Good start! I already had this setup running a 2000 MHz with room temperature water, so I set the FSB and multiplier slightly lower (12.5 x 157) and booted into Window’s no drama’s.
MBM temp’s showed that, after 4 hours of running Sisoft Sandra, playing a couple of games, etc, the temps got up to:
Next day I pushed the CPU as far as it would go: 2187 MHz (real ones, not AMD ratings) but not stable. I had to drop all the way back to 2100 MHz to get it completely stable and have had it running at that speed for some months now. It could due to the PC2100 RAM I am using. While the results are nothing startling, at least I satisfied my curiosity about:
- Running a computer inside a fridge
- Lowering temps to get me another few percent out of a processor that should be running a 1466 MHz.
And as I live in Thailand and the summertime room temperatures in this house get up to 40 C, the fridge does a nice job of keeping my system cool and condensation free.
About the temps which you may not want to believe… take a good look where the condenser (icebox) is and think back to some older articles about putting the condenser in the water to improve cooling capabilities of the fridge as we know it.
David Curtis – Thailand