My first forray into below ambient cooling

I'm building my next system soon and need to know what kind of cooling I'm going to use. My ideas for phase change have been shot down by mom and dad due to the extreme power usage of refrigeration. I'm now looking at peltiers for a water chiller. (Don't anyone correct me, *I* know they're much less efficient to get the same job done but THEY don't, and THEY'RE paying the bills.) to create a water chiller.

I'm looking at 1 of these 350W 62MM monsters off of ebay, and need to know if air cooling will suffice or if I need to go buy a water cooling system for the peltier itself. My plan was to go to the junkyard and dig up some good oversize heat sinks to put on the peltier, and use some spare 120MM fans.

I also want to know if there is a way to throttle down the peltier so that it isn't constantly cooling at maximum capacity and thus not drawing as much power.

Alright, onto the mechanics of what I'm planning.

The 350W peltier will be attached directly to a copper reservoir on the cold side, and the heat sink will be on the hot side. This will be in a micro ATX case under my main case, which will be acrylic. (I'm planning on making this look a lot like one of the phase change systems on the market today, even though it's just a water chiller.) The case, being acrylic, will be easy to seal off. The water cooling loop will cool all major sources of heat (CPU, GPUs, northbridge) and will be uninsulated.

Am I just being stupid or will this work? I hope I described what I'm planning well enough, poke holes in it so I can fill 'em!

This will be going into a high powered SLi system. If I need to I can scratch the sealed off case idea and just insulate where I need to and have airflow inside the case, but I'd prefer not to have to put anything on the board that would damage its resale value.

Anyway, if you guys can find a low enough powered compressor that will draw less than this peltier plate, tell me!

you can get a cpu to below zero using a 150-200w peltier on a copper or alluminium heatspreader, say 10mm thick, and water cooling on the hot side of the peltier.

air cooling is not good enough for peltiers, unless you put a powerful heatsink (thermalright ultra 120) with a big loud fast fan.

i had some links to a review where experments were done with water chilling and the conclusion was that water is great at absorbing heat, but you need a lot of power to cool down the water. thats why it's better to let the peltier cool the cpu down and the water absorbs the heat from the hot side of the peltier.

water cooling on a conroe without peltiers will give you great results, without the hassle of having to insulate everything from condensation, and electricity bill savings. might be better to invest in getting good pc hardware instead of extreme cooling hardware.

Alright, thank you. I enjoy doing both, and I love building things. It wasn't out of necessity that I was doing this, heh heh.

Well, a water chiller would be good to allow you to run low temps without running the compressor all of the time. Refrigeration systems dont have to be heavy on power. When I started my water chiller idea, I did some research on power rates. You can go to your power company's website and find out how much it costs per kilowatt hour.

Now, most of these systems use a compressor that you would see in a refrigerator. Say you get a 500 Watt compressor. Now thats pretty high, probably around a 1/2 HP compressor (which you dont need unless you're me). But it makes the math easier. Anyways. Say its rated to 0 degrees F, that means to maintain the pressure neccessary for 0 degree evaporation temps, it requires 500 Watts.

Our power company charges 7.5 cents per kilowatt hour.

Lets say you run your computer for 10 hours a day straight, then turn it off. Given an average consumption rate of 500 Watts per hour, that means 1 kilowatt hour is 2 hours of time. That will mean 7.5 cents per 2 hours, and 37.5 cents per day. That translates to 12 dollars about per month.

Now, that isnt a static figure, But for the size of compressor that you would run, probably 300 - 400 Watts, you could offer to pay the balance yourself. If they try to compare it to A/C, remind them that those compressors are 3 - 5 Horsepower, and utilize much more power than a refrigerator compressor.

I'd say youd probably wind up with a 20 - 30 dollar power increase a month. Now, I remind you this is text book only, I havent yet tested my theory. But I assure you, it couldnt possibly equal that of an a/c unit.