Do-it-yourself CPU Water Cooler

Foss writes "This article on EIMod.com shows a (very) cheap and effective way of getting that usually-expensive water cooling system that many of us have thought about. There are some pretty pictures too :)"

Comments

cheap and easy...

[doooras]

just cover your hardware in saran wrap and dump ice in the box. works like a charm to keep it cool.

Instructions that you don't want to see

[hij]

use a double knot to stop the string coming undone and use only cotton string!

These are the sorts of instructions I don't like to see in a mod! At least it doesn't mention chewing gum...

Liquid Nitrogen Cooling

[Davak]

Why go to all this trouble? This is obviously the way of the future. :)

Eeek!

[JimPooley]

The words 'cheap', 'water' and 'computer' used in close proximity do not inspire confidence or an incentive to try this mod out.
Then I read about the cotton...!

Has anyone just stuck the board in the fridge?

[sdo1]

Just sticking the CPU board into a mini-fridge would be cheap and would probably work pretty well. Plus any extra space could be used to keep your beer cold.

-S

What cools the pump, an underclocked '286?

[Tall_Rob]

Okay, so his water pump is only designed to run for a max of 10 minutes before overheating. Since overclocked CPUs generate heat, an underclocked CPU must be able to absorb heat, right? RIGHT? Why not slap an old 286 onto the pump, underclock it to run at, oh, say, 2 Hz (not mHz, but plain ol' Hz) and the 286 will absorb all the excess heat off the pump! Voila! :-)

Or should he just get a water cooler to put on the pump, which would in turn need a water cooler for ITS pump, which would need a water cooler for ITS pump, which would . . . oh, wait, this is infinite nesting, isn't it? :-P

Re:What cools the pump, an underclocked '286?

[markmoss]

No, what he needs (and no doubt he is aware of it), is a better pump. Also proper tubing fittings, hose clamps, baffles inside the waterblock to direct the flow so all of it gets cooled, ears on the block to attach spring-clip heatsink holders, and so on. But the cheap 10-minute pump is good enough for checking out whether he's on the right track -- and he claims his budget was 77 pence, which I think is about $1 US. Aquarium pumps run continuously and aren't too expensive, but on that budget you use what you already have...

I do hope that he used thermal grease -- the article doesn't say one way or the other, but even a perfect heat sink can't cool well if the heat has trouble getting _to_ it.

One thing that did kind of bother me: "Although it seems that copper would be best suited for making a water block, I'm not entirely convinced without physical proof." It scares me that anyone who has to ask would be doing this! Copper is indeed the best material, unless you are on a NASA cost plus 10% contract, then use gold and increase your profit. ;-) Copper is resistant to corrosion and has the second highest heat transfer rate (by volume) of any material available in bulk. Gold is better and aluminum is worse on both counts. When aluminum is used instead of copper, they are trading off a little effectiveness for considerable savings in cost and weight; if you are using water, weight better not be an issue, and for a do-it-yourself project you'd spend a lot more trying to solder aluminum than copper will cost...

Why water, try oil.

[bluGill]

Water conducts electrisity. Well, pure water doesn't, but pure water will eat metal until it does conduct. That means you have to keep your water carefully sererate from everything else.

By contrast, oil doesn't conduct, doesn't disolve metal. Fill your case with oil, and you have better cooling than air, and much easier to deal with. (Note, oil isn't as good as water for heat capacity, but it is still better than air and has all the other advantages)

Re: Why water?

[Wingchild]

Water cooling requires that the water, passing nearby a heat source, absorbs the heat and carries in on to a place where it can be safely transferred into the surrounding environment. The old Second Law, Energy can neither be created nor destroyed, etc etc.

So why would we opt for water, which would be a less than optimal coolant? Because hot water makes *coffee*. Imagine! You could have a water-cooled server *and a coffee machine* all in the same rackmount!

The possibilities are endless.

Watercooling works great

[xtal]

I run a watercooled machine as my primary work box. It's great, and the noise savings were incredible. No more whirrrrrr. Fits snugly into a standard mid tower case.

I have a page up with all the details of contsruction for you who are interested. I've been running it for a few months, 24/7, and there have been no problems whatsoever. I took a few additional precautions, but the system as been moved around several times without any difficulties whatsoever and I highly recommend it to others who are interested.

Re:look at what I found on eimod.com

[stoolpigeon]

These guys have some time on their hands.

That's cool though- they are just thinking up ideas and trying them out. They are not worrying too much about convention apparently.

How many great ideas started that way?

More than I could name.

.

Hydroponic CPU's

[muerte24]

i built a water CPU cooler for $20 out of pocket costs. of course, that doesn't count the stuff i stole from work. :) it's a machined copper slug, a reservoir, and a $20 aquarium pump.

if you turn the thing on with a cool reservoir, the CPU temp stays below 76F. but after being on for 10 hours, the reservoir temperature raises to about 113F due to my lack of money to buy a real radiator. so my equilibrium CPU temp with an Athlon XP 1600 is 123F, when the fan it came with ran it at 145F.

you can see pictures and stuff here.

granted, copper slugs and machining equipment and "free" swagelock (and peltiers!) is not something everyone has, but use what you got, right?

hope someone finds it useful or interesting.

muerte

Ouch!

[Verteiron]

"1 - 3 grams of solder should be enough, but it's always best to buy excessive amount just to cover yourself."

Maybe it's just me, but wouldn't covering yourself with solder hurt like hell?

You don't need a radiator...

[Exedore]

...to shed heat from the coolant. Just run the water coming from the cpu to a shower head (or similar) suspended above an open reservior. The water is dispersed by the shower head (increasing surface area) and cooled by the air as it falls into the container below.

Granted, this approach requires an open reservoir outside of the case, but it's simple, effective, and cheap.

Bonus: it can also replace those stupid "Sounds of Nature" tapes that people use for background noise at bedtime.

This story actually teaches a lot...

[jhiv]

This story actually teaches a lot about how not to build a water-cooling system for a CPU.

Some specific observations:

1. The low delta T (temperature difference) for the water going through the system is a sure indication of low efficiency. The most likely culprit is poor contact between the block and the CPU. Thin sheeting was used, and ripples are clearly visible in the pictures. The block is probably only touching in a few places and there is no mention of using thermal grease. A stiffer bottom plate was clearly called for.
2. As mentioned elsewhere, hose clamps should have been used. (String? Let's not go there...)
3. There is no radiator to dump the heat back to the environment. The heat transfer from the surface of the tank is probably not sufficient to keep the temperatures low. The radiator should be after the pump, to dump the heat from the pump also.

Perhaps the story should have been posted with the "laugh, it's funny" icon.

BTW, I prefer Indium foil as the thermal gasket between the CPU and heat sink, not thermal grease. Unfortunately, Indium is usually as expensive as gold.