Watercooling

[Variable]

I just build my first watercooler and it seems to be running fine. But frist I want to know if I did everything right and if you have any tipps.

My System goes like this: waterpump in a empty can (holds approx. 0,3 l water or coolant) -sitting in my Big Tower- from there it goes to the CPU-Heatsink (an empty aluminium-candy-box/can sealed thight) from there it goes to a hole in my Tower-case. There the hose runs in circles etc. and is cooled by a fan blowing into the tower. The hose stays in the tower and the fan is mounted from the outside on the case (maybe I will widen the hole and attach a second fan). From there the hose goes back to the can with the waterpump.

Should I use water or coolant used in cars or maybe both?

Do you know how a refridgerator stays cool? I believe there is a chemical in there that is pumped around and generates cold when it is stirred (pumped). Maybe I could use that??

[dexmax]

A refrigerator...

Well normally heat travels from the hotter body to the lower body. This is a Law in thermodynamics. But when you do some work, you can reverse the process.

A compressor is used to compress the working fluid, R-22, R-143, R-12, amonia, etc. adaibatically. This means without adding or removing heat. Thus the pressure is elevated, likewise the temperature is elevated. The fluid will become superheated from saturated vapor after compression.

Now the fluid will go to the condenser where it will be releasing Heat. The fluid will decrease it temp until it reaches saturated vapor state and will maintain its temp, still rejecting heat, until it becomes saturated liquid, or even sub-cooled.

It will now pass through an expansion device, a capillary or an expansion valve. It expands adiabatically, pressure is dramatically reduced, so the tempearture goes down. Now the fluid is now a mixture of gas and liquid.

It goes to the evaporator, where it accepts heat. Thus, the fluid boil in the process until it is saturated vapor.

Then it goes back to the compressor, and the cycle continues.

Any Questions?????

[CMonster]

Technically accurate description of refrigeration .. but ..sheese! could you have possibly dumbed it down a bit for the benefit of those not certified?

Basically these "refrigerants" have a unique pressure temperature relationship so that at lower pressure (in the evaporator - the thing that "gets cold") they can absorb a whole bunch of heat and then they carry it to the condensor (the thing that gets hot) where they usually transfer the heat to the air. A cycling pump in these systems usually keeps things circulating as necessary.

Liquid cooling, or a raditor type system, works in a similar way but without depending on pressure difference - it just picks up the heat at one place and carries it to a place where it can be dissipated - usually radiated into the air. The pump usually works continuously in these systems.

Most of the "home-grown" liquid cooling systems that I have seen for computers/CPUs consist of a large tank of coolant from which the coolant is pumped through tubes to the heat source and back to the tank - this system lacks sufficient means of getting rid of the heat once the coolant/liquid is saturated with heat - in short, they need some kind of radiator.

I'd like to see some pictures of your system - why not post them here?



[This message has been edited by CMonster (edited 06-10-2000).]

[Variable]

Thanks for the description of how a fridge works although i didn't understand nothin'.

My System is not fully finished jet but in the final testing stages (I will get pics as soon as I'm satisfied it really works).
My problem right how to take the heat out of the coolant.

1. Running the tube through another metal box/can for cooling is better than the rubber tube I use. Don't you think?

2. Putting a fan over this metal box/can?

3. Putting this box/can into a bigger box, can etc. with more water or coolant

... any other suggestions?

[Biff]

refridgerator wise Variable, the gas pressure will roughly equal temp.

I would recomend using a used cooler from a cars trans cooler to remove heat, you would need to hook up some kind of fan to draw air through it.

[cpucook]

A simple water cooler is the way to go.....much safer than using a compressed gas, too. I think that you will have a heat problem though, because it does take a REALLY good radiator & pump to cool the water as it returns from the cpu at about 10 - 15f warmer.....with no radiator, my k6 2 450 @ 550 will overheat in just UNDER 2 HOURS...I have two Ford transmission coolers, with two 4" fans on each one...One radiator cools the water going to the cpu, while the other one cools the water going back to the tank.....and, IMO, you'll need about two gallons of water in the system, and your pump SHOULD move no less than 40 - 50 gallons per hour.....but you'll want 70gph to get REALLY GREAT cooling.

......BUT, thats just my opinion though....I am known to be a bit too enthusiastic about my "home brew cooler" :-)

Have fun,
cpucook

[Variable]

I got myself the cheapest waterpump I could get: 9,95DM = 5$
it runs on 220V (3.8 Watt) and pumps about 300 liters an hour (~66 to 80 gallons per hour).
I wanted to use up as little space as possible because I want to place the whole system into my PC Big-Tower Case (AT).
I tested the CPU Water-Heatsink with a lighter and I couldn't even make it warm.
My total watercooling-system uses about 0,5 liters of coolant.
I will take up your idea of an car-trans-cooler but how much space will it need (I wanted to make a hole on the side of my PC-Case, put a fan on the outside blowing cool air in and cooling the watercooling system.
I wanted to place a metal box, metal tube etc. right under the hole so the fan on the outside cools it (side-effect it also blows cold air past the whole sys into my case).

Do you think that will be enough. I want to overclock an AMD K6-2 533 as high as it goes (600 MHz and up - although I think the board goes only up to 133MHz FSB => 798MHz CPU).
Currently I only run it at 410MHz because I'm waiting for this new mobo (DFI K6VB3+ 66) and it barely gets warm. So I hope my little water-cooling will will be enough.


What I'm working on beside my watercooling-system is a hairdryer-fan. You surely used one once in your life.
And gosh, these things have power.
And they only use 12V!!
I have on in my case but I don't use it because it is too loud (sounds like an airplane). But if I could quiet it down I would use it to cool my watercooling system.
Do you have any suggestions how to quiet this **** thing down (although I think the sound comes mainly from the air it pushes).


[This message has been edited by Variable (edited 06-11-2000).]

[Variable]

By the way, if I put a fan on top of the watercooler box on my CPU won't it achieve the same / better results than a standard heatsink with fan? It works the same way except with a watercooler-HS the HS itself cools too.

[cpucook]

My k6-2 450 would not hit 5.5x95 @ 524Mhz without the water cooler, now it will run at 5.0x112fsb @ 560Mhz, and at full load, cpu temp is never more than 84f......BUT, I could not keep the cpu temps from slowly rising, and eventually causing a crash....SO, I doubled all my fittings & hoses, added the second tranny cooler, and added another gallon of antifreeze to my tank, and I can just now run at 5.0x112 2.8v without overheating.

I just ran at 6.0x100 2.9v @ 600Mhz a few minutes ago......and I got into Win98 for about 5 minutes before the heat was catching up to my cooler, so I set it back down.....for now :-) BUT I know 600 can happen, but I'll need a few trays of ice in my water tank :-/

If you get just 1 liter of water to cool your cpu during overclocking, I will be very suprised......I'm going to switch to a 5 gallon tank, that MIGHT allow the water enough time to cool before it goes back through.

Happy clocking! (Hard-Bioled cpu)
cpucook

[CMonster]

Keep as much stuff outside your box as possible.

Never allow heat to dump inside your box if it can be avoided.

My advice is to dump the 220v pump (in favor of a DCv model) or make sure it is installed on a ground fault interrupter of some kind.

Sorry to be the one to break this to you but the K6-2 533 CPU will not likely go over 600mhz and will probably never be completely stable at 600mhz even if you freeze it.

If you want extream overclocking for about the same price, without having to use water cooling at all get a CeleronII and a 133mhz motherboard. Even without overclocking the performance is substantially higher. Persoanlly I like the Iwill VD133.

The good news is that if you perfect your liquid cooler then it will fit on the Celeron, PentiumIII, and new AMD chips.

[Grant]

FYI water is a much better cooler than antifreez/coolant. Coolant is used to prevent corrosion and lower freezing temp.

[Keermalec]

I think the main problem you will have with a custom built water cooler is the radiator. To cool off water that is only 10-20° above room temp you will need a good radiator like 3dcool's:

http://www.3dcool.com/prodimg/radiator.jpg

see: http://www.3dcool.com/radiators.shtml

The fins take heat away from the water tubes just like a regular CPU's radiator does. A simple tube running in loops will probably loose heat much more slowly. If you're ready for it, I would try to build a radiator or get one from the back of an old fridge.

[This message has been edited by Keermalec (edited 06-13-2000).]

[dexmax]

Keermalec, that's cool. I never thought of using a radiator for my pc, but maybe i will sometime. but not now i think.