Anyone Peltier instead of using a radiator?

I have a 1700+ Thoroughbred CPU that hits 2GHz with a cheap aluminum cooler, but isn't quite stable. I'd like to water cool it, but I was wondering if anyone here has used peltier(s) to cool the water? I would think a peltier would work as well or better than a radiator.....

A peltier pumps heat from its cold side to it's hotside. It does not absorb heat. It takes substantial power to run a peltier also, and this also shows up as heat on the hotside of the peltier.

The hotside of a peltier needs a substantial cooling system.

I think you misunderstood....

maybe a drawing perhaps? I left out the water pump to simplify the image a bit.....just pretend it's there....



The cooler for the peltier array would be 2 large aluminum heatsinks. The peltiers would be 2 50W units. They would be sandwiched between a heatplate and the water jacket.

Has anyone tried this?

people have tried that, yes, Its extremely innefficient, and yes He understood you perfectly,
theres no way 100watts of peltier cooling will cool your cpu, You need more like 300 or so.... take that into consideration...

Why? No CPU puts out 300W of heat!?

Oh, and peltiers are ELECTRICALLY inefficient, but are still excellent cooling devices....

how many watts of heat would be in the water for the XP listed above?

According to AMD, a 2.133Ghz 2600+ cranks out 68.3 Watts at Maximum with stock voltage. I'd like to know how much 1.9V increases the thermal output of the chip...

I'm not looking for subzero coolant temps here.....just sub ambient temps, something you'll never EVER see with a standard radiator.

http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/25175.pdf

Link to Tbred Whitesheet, its on page 23

I believe you hit around 100 watts if your pushing 1.9 volts overclocked to 2Ghz. The 2600+ I think is at a 1.6 volt for stock.

There is a site on the net somewhere that calculates what kind of heat you would be facing giving the voltage and overclock settings. I can't remember where I seen it though.

Do you or anyone else know if there is anybody around who has used my idea already? I'd like to see an example before I try it.

ok, so if your gonna only put out 100 watts, then you need almost 2x the cooling because of how innefficient it is to trancefer to the water and all, ITs tons more efficient to use it directly on the cpu, There are peltier controllers so you can set them to whatever you need...

I dont think it ineffecient at all.....

Farleytron said:

The cooler for the peltier array would be 2 large aluminum heatsinks. The peltiers would be 2 50W units. They would be sandwiched between a heatplate and the water jacket.

Has anyone tried this?

Click to expand...

Yes people have tried stuff very similar to this. Most have been very disappointed in the results.

As JFettig said, two 50 Watt TEC's is not enough to get any benefit.

The heat pumping capacity (Qmax) of a TEC is measured with a temperature differential of zero. In other words, if the two 50 Watt TEC's are taking 100 Watts out of the CPU, the temperature difference between the hotside and coldside of the TEC will be 0C. (If you are maintaining the hotside at around 25C. Which you won't be by a long shot.)

You need much larger TEC's and much better hotside cooling to have any chance of outdoing a radiator.

I had a "smarter" version of this idea before:

http://forum.oc-forums.com/vb/showthread.php?s=&threadid=151987

and it still was a bad idea. Stick with the radiator.

TEC chillers are very inefficient. I have a Full fledged 675 watt Thermoelectric water chiller and its roughly as good as a radiator cooled 226 watt Peltier directly on the CPU/Waterblock. With my P4 2.2@3GHz and water at 7-8c I get CPU temps around 20c. If you only use a low power chiller to cool your water it will be worse than air cooling. The only practical solution is to cool the water with a radiator and then send it through the TEC chiller. This should drop you several degrees but your not going to go sub ambient.

Check my sig for the chiller!

I STRONGLY recomend that you put MUCH more research into this before dropping your hard earned cash. If the cash is no big deal if (or when, rather) it fails, then by all means do your little experiment.

The reason that you need so much better cooling and they are so inefficient is because you have to dissipate the heat from the cpu PLUS the heat generated from the TEC!

BTW if you use 50 watt TEC's off of your power supply, you will not see the 50watt rating (unless they actually make them for 12volt instead of 14 now) So really you're looking at 80 watts or less.

Anyway... Good luck if you do it, but it really is just not going to work.

I was going to use a separate PSU to power the 2 TECs.....

I'm just confused why everyone is so adamant that 2 TECs can't be better at cooling water than a crummy radiator?? And actually, after looking at some other peltiers, I will probably purchase 2 76W 40X40 TECs simply because they are not much more expensive.

Do you guys honestly think that a room temperature cooled radiator is superior to 2 TECs? Can someone point me to a website-based that proves this point?

I mean, the whole point of using water cooled by peltiers is to have the coolant stay cool, AND if the pump or the TECs fail the system should overheat gracefully allowing the motherboard over-temperature shutdown feature to actually work.

Do a search on pelt, tec, peltier, chiller. You will find a lot of information. Obviously you want to be in the extreme cooling section as well.

How much research have you put into this? Seriously, don't just read the specs of something and think you know everything about it... A LOT of people have tried this and failed...

A mini fridge sounds like a good idea too, but it isn't... Be cool, man. YOU do some research, don't make US do it for you.

I'm probably failing at trying not to be rude, but at least I'm trying...

Farleytron said:

I'm just confused why everyone is so adamant that 2 TECs can't be better at cooling water than a crummy radiator?? And actually, after looking at some other peltiers, I will probably purchase 2 76W 40X40 TECs simply because they are not much more expensive.
Do you guys honestly think that a room temperature cooled radiator is superior to 2 TECs? Can someone point me to a website-based that proves this point?

Click to expand...

TEC's are awesome little devices. They pump heat from one side to the other, but at a great cost in efficiency. I've heard mentioned they're as low as 20% (or less) efficient.
Now the problem with building a pure TEC radiator is that you'll have a really difficult time in getting enough surface area meeting the water to extract it's heat. Radiators are built for air and can be any number of shapes, but to find a shape that's got both humongous water surface area and a 40mm square area on the other side of it is a daunting task, even for engineering and R&D departments. Air works easily because it's a fluid (so to speak) that can be blasted all over whatever surface we decide using the brute force of a fan...not so easy with a 40mm square piece of ceramic.

You starting to get the idea? Even a small computer fan can push 30 cubic feet of air per minute, yet the TEC is still using the static 40mm square. It's not that the design of a radiator is more efficient, it's that it's cooling medium is easy to work with, pliable, and can "brute forced" with the cheapest of equipment, the lowly fan.

I had seen a web-page at one time, where two students used a TEC to cool a single processor with an HSF mounted on it, all hanging out the back of a computer.
The problem translating that idea to an Athlon is that that was a pII 300 processor, which drew almost as little wattage as the case fan did. Their processor still got pretty warm too.

I'v had an idea of using pelts as a rad for a while now and this what I'v come up with. this is the rad assembly, start with a water block with the AMD mounting holes, ex DD maze 3, then get a swiftech MCX462+T and a delta or tornado. attach the base of the maze3 to the cold plate of the MCX, this is all held together by 4 bolts running through the AMD mount holes. Put the fan on and put it in as intake. The MCX has a 226 pelt standerd. http://swiftnets.com thats my idea, but it wont be cheap.

Does anyone know how to calculate the hot side thermal output of a peltier at full load (maximum)?