Peltier plates for CPU cooling, are they worth it?

I have known for a long time about thermoelectric cooling, and I am well versed in the underlying technology. I, however, assumed that the technology had not matured enough for use in consumer electronics outside of some low efficiency camping/car fridges.

That was until I came across this website while doing some research for an electronics project:

http://www.frozencpu.com/cat/l2/g30/c105/list/p1/Liquid_Cooling-Peltier_Coolers_TEC_Coldplates.html

I have a 750 watt power supply and since I only use about 400 watts with everything maxed out I was thinking this might be a great addition to my gaming rig (sandwiched between my H100 cpu cooler and the cpu). It is my understanding that peltier plates are capable of up a 70c (158F) reduction in temperature, which if the plates listed are even capable of 50% of that reduction this would be an amazing improvement in cooling capacity.

My question to you is, In your opinion, are these thermoelectric coolers worth the $43 price and the watt usage?

 

The plate takes the heat away from one side, and moves it to the other. One side is really cold, the other side is really hot. So i really dont see how its better than direct contact. It will create a lot of heat (the same amount as it cools from the other side). So, your CPU may be cooler, But I doubt that your cooler could keep up, honestly. 

(Take my words with a grain of salt, I've never used one, going off of theory)

The problems are condensation, heat, and cold. No really!

The Condensation problem is because one side is so freaking cold and it turns all the air into water... right where it contacts the cpu with all of the connections and stuff that break when wet.

The really cold creates cold boot issues probably the least worrisome thing of all the problems.

The really hot can destroy your computer if for a minute your heatsink fans or way liquid cooling stop working. And I say fans because one ain't enough.

Together, the really cold and the really hot create a terrible inbalance in heat transfer whent he computer is at different loads. This imbalance can completely break the physics that make the peltier solution work. To learn more, ask google cuz I could try and regurgetate the physics but I'd be making things up (There is a LOT of physics to it).


Unfortunately, right now there is truly no good, viable option for peltier cooling as far as I'm concerned. Absolutely phenomenal concept that is perfect in theory, but way to difficult too employ in the real world because it's just so extreme. The most difficult thing to fix is honestly the condensation problem and the mixed balance of heat when running at different loads. 

Peltiers for CPU cooling are severely counterproductive, because they just add a whole lot of TDP to your radiation load.

The way a peltier element works is by running current through a medium from one type of metal to another, and that concentrates carries all the energy, in the first place thermal energy, from one side to another. That means that the thermal energy of one side is evacuated to the other side, but on the other side, the thermal energy that has to be dissipated, is equal to the TDP of the CPU plus the thermal energy of the electric current the peltier element itself uses, and peltier elements use pretty much electric energy for what they do (which is why peltier elements are not used in fridges anymore since well before WWII). In fact, CPU cooler with heatpipes use exactly the same technology that is used in modern fridges, namely ammonia evaporation and condensation, except without compressor, because even though a compressor uses less electrical energy in relation to the benefit for thermal transport than peltier elements, fact is that it still adds thermal energy to the radiation part, which in fridges is about the size of the entire back panel, and a fridge has to provide a smaller Delta t° than a CPU cooler... so heatpipes use a passive ammonia transport system that doesn't require external energy, in the form of a capilar pump, in cheaper heatpipes that is a wick in the middle of the heatpipe, in more expensive designs that is a combination of a wick and a microporous ceramic compound coating on the inside of the heatpipes. That capilar pump brings the condensate back to the thermal interface plate where the condensate evaporates by absorbing the thermal energy, which is then transferred to the radiation side, where the coolant condensates, and is pumped back by the capilar pump or just flows back by gravity. So the only thermal energy that has to be radiated by such a design, is the thermal energy added by the CPU. That is also why the CPU temp in a room that 2 °C hotter, will be exactly 2°C higher than in the 2°C colder room.

You're mostly right, but what you're missing is the fact that it removes heat much faster then conventional CPU cooling systems at the cost of extra wattage. While this will mean more heat on the cpu cooler then in a normal situation, I can't see any decent CPU cooler, like my corsair H100, being bothered by it. The cpu cooler can handle the Heat but it can't draw off as much heat as quickly as the plate can because a normal CPU cooler relies on passive cooling rather than the plates active thermoelectric cooling.

To narrow it down to shear basics, the peltier plate is taking heat from the cpu and electrically pumping it into a system that can handle it, but otherwise couldn't draw off that much heat that quickly on its own.

Now this is assuming we are only talking about the peltier plates I linked to, since they were designed solely for CPU cooling.  

if condensation is such an issue, then why do sites sell them? Surely nobody would buy them if this was an actual problem that occures.

Also the imbalence could be solved with a simple feed back circut tuned to keep the temperature within a desired range. This was something I already thought of before I first saw these for sale (for another application I was reserching).

I assume most people Pick their PC parts with large margins of safty in mind. I picked out my cpu cooler knowing it was far more then my cpu needed. I personally belive that large amounts of overkill is a far better solution then finding out later on that something isnt good enough in a system that you have already finalized. So I personally dont mind if my thermal output is higher so long as my cpu runs cooler becuase of it. I build gaming rigs for performance gaming, not becuase I care about its energy consumption or the amount of heat it generates. That is honestly the last thing on my mind so long as the CPU runs cool and stable.
 

I'm by no means an expert on peltier coolers, but I'm not sure you need that level of cooling unless you are going for some truly insane overclocks. You'll need a really good liquid cooling system just to cool the hot side of the plate. You will not only have to be able to remove the heat of the CPU, but now the quite substantial extra heat put out by the peltier. If you would apply that liquid cooling system directly to your cpu you would get MUCH better temperatures than you get with your H100i which gets outperformed by some air coolers. A custom watercooling loop would get CPU temps as low as you need them for a gaming machine. I think peltiers are designed more for people that want to simply overclock as far as they can for the sake of overclocking. 

As for the safety of extra cooling, I'm not sure I would call a peltier the safest rout. 

Condensation almost certainly will occur at somepoint, and your components better be well insulated. Check out the end of this video.

Some other things to consider if you buy the $43 unit.

You will need a custom watercooling loop to cool the hotside of the peltier. Rough estimate $200

You will need a way to power the peltier. That will probably mean an external power supply. FrozenCPU sells one for $150. 

So I think that $43 unit will cost you closer to $400+, and that doesn't even include the new electric bill. 

Again, as long as you aren't going for a crazy overclock, I think a custom water loop will keep your temperatures as low as you could want for less money and less risk.

Well thanks for the info guys. I'm just going to drop the idea since all I've gotten is negative responses. I have no intention of overclocking, since my 8350 Is more than fast enough on its own, so all in all it would only be impractical since I would have to wire up custom circuitry to keep the thing stable. Honestly I just wanted it to be usable since I dislike the idea of water cooling. The closed loop corsairs are about as close as I want to be to liquid cooling.