Phase change cooling

[owen]

Has anyone tried phase change cooling? How easy are they too install? I know that you can achieve sub zero temperatures which obviously has overclocking benefits but many people say stay away from it. But why?

[jdrom17]

Well it's expensive, uses a lot of power and is noisy. Basically its like having your fridge run 24x7 with a lot less insulation and what not to lower the noise.

If you have the money and can deal with the noise and power bill, then it's a good way to cool your CPU I guess, but you might as well go all out with some LN2 ;)

[yahooadam]

well its not _that_ expensive (in terms of running costs), but it is as costy as having a fridge on at the same time as your PC

But the risks have never seemed worth it to me (condensation) and PCC's are expensive ($1k ish)

[Assimilator87]

People have told me that leaving the fridge door open would burn out the parts real quickly. If that's true, wouldn't phase change coolers on CPUs run into that problem even quicker?

If you want phase change cooling, but don't want to go through the hassle of installation, get this :redeye:: New Biohazard Desktop @ Fudzilla (http://www.fudzilla.com/index.php?option=com_content&task=view&id=5103&Itemid=1)

[Avid6eek]

Has anyone tried phase change cooling? How easy are they too install? I know that you can achieve sub zero temperatures which obviously has overclocking benefits but many people say stay away from it. But why?They cost alot, are loud, and I would assume they are one of the least reliable cooling methods. Condensation was mentioned, but as long as you follow the directions and install it correctly, that isn't a problem.

People have told me that leaving the fridge door open would burn out the parts real quickly.It is more like a small AC unit than a fridge. Leaving an air condition on constantly won't damage it as the components are designed for a continuous duty cycle. Phase change coolers electrical use is more comparable to an air conditioner than a refridgerator, which is why it's so expensive to run.

[AlphaChicken]

Yea the compressor has to run pretty much all the time in a phase change. Whereas the one in a fridge only has to run every once in a while to bring the inside temps back down.

Insulation isnt a biggy. As long as you use dielectric grease in the socket and such, and use neoprene insulation in the proper places, no cold will be lost to the surrounding air and no condensation should occur. Except in the socket, where there is the grease to protect from it.

They are expensive to buy. Not so much to run though. I knw people that run them 24.7. The bigger units (cascades) can reach temps of -120c but they utilize stages within the phase change process. Each stage needs a another compressor usually (a normal phase change is called a single stage and has ONE compressor). So these cascade units use up ALOT of power. Definately something that is more for benching than 24.7 use.

Single stages can usually hit anywhere from -40c to -60c. The temp isnt really what matters though. It is the heat load that the unit is tuned to in watts. Temp is somewhat irrelevent to performance but not completely. Temp depends on gas used for the phase change and each gas has different tuning properties compared to its temperature properties. For example you could have gas1 tuned to a 150 watt load at -60c and gas2 tuned to the same load at -38c. both units would perform exactly the same. Basically, if a unit advertises it hits -80c, it doesnt mean it performs well!

Phase Change is not something that is worth it for the average user. I was going to build my own unit but required about $3000 worth of tools. PLUS the supplies I needed to build the unit. I could have built a unit for about $400-$500 (supply wise) but the tool overhead wasnt worth it seeing as i only planned to build one unit. If you cuold find a way to build a cheap unit without the tool cost it would be more worth it.

If you are buying your own unit, the retail ones absolutely suck. They are tuned for crappy loads. This is one bad, because if you overclock you are stuck within a certain load range that will be hard to determine and you could possibly kill your machine. and two, because every proc has a different heat load range, so its not as good as getting a unit tuned for your exact proc.

The custom built and custom tuned units are great and ALWAYS work good. the problem is that they are expensive and it ccan be hard to pick a very reliable builder, as you are not buying from a company, you are buying from a normal person whom you have to be able to trust.

hope this helped some people out. :)

[yahooadam]

the PCC should cool down the motherboard enough to cause condensation

I know some of them use a Heater Element around to the board to stop it, and others just use some insulation

I forgot the fact that fridges only run occasionally ;)
In a fridge, cos its not running 24/7 it gives it more time to cool down the liquid in the circuit, but in an Air Conditioner (or pcc) they use fans to cool down the heat sink (or pipes) so that the liquid is always cool enough

[AlphaChicken]

I know lotsa people that run em 24/7 and have no heater coil (usually only in retail units for liablilty things) that have no problems with condensation. As long as you insulate correctly.

[owen]

They cost alot, are loud, and I would assume they are one of the least reliable cooling methods. Condensation was mentioned, but as long as you follow the directions and install it correctly, that isn't a problem.

Where does the condesation form?

Well it's expensive, uses a lot of power and is noisy. Basically its like having your fridge run 24x7 with a lot less insulation and what not to lower the noise.

Noiser than having 4 fans on the go?



Phase Change is not something that is worth it for the average user. I was going to build my own unit but required about $3000 worth of tools. PLUS the supplies I needed to build the unit. I could have built a unit for about $400-$500 (supply wise) but the tool overhead wasnt worth it seeing as i only planned to build one unit. If you cuold find a way to build a cheap unit without the tool cost it would be more worth it.


Thanks guys some useful information there. I have seen those vapochill kits which have everything you need to get started. Are they not worth a look? Also what about refiling them? How often and how risky is it refilling them?

[Assimilator87]

I'm pretty sure you have to take it to a professional to have the gas recharged so there's really no risk. I think it's cuz you have to have a licence to get a hold of the refridgerants.

[AlphaChicken]

Lol. I have a liscense for purchasing refrigerant. Just dont have the money or tools to actually build one of the damn things... >.< took the test for it. Its no prob really if your serious about it and study to really learn the stuff. However I wouldnt recomment re-filling for a normal user. :)

I wouldnt really look into the vapochills. not really worth it. If you were ACTUALLY going to get one, I would go over to xtremesystems.org forums and see if you can find a builder to build you a really nice one tuned for the CPU you need. but once again it will be expensive and not really THAT much better over air until you start going into multiple stage units such as cascades which would cost even more and not be for 24/7 use.

Condensation forms inside the hermetic cell formed around the socket and processor. It should be hermetic anyway. Thats why you put the grease in there. It is non-conductive and protects everything in there from corrosion. condensation can also form on the outside of the suction line and the back of the evaporator head if they is not properly insulated. Usually to completely make sure this doesnt happen (good insulation done properly will do the exact same thing just as good), retail companies use heating line/a flat heating element on along the suction line and on the back of the evap head respectively.

[owen]

so have you embarked on a phase change cooling system ?

[Assimilator87]

Remember when OCZ announced that they were working on a PCC in the $300 range or something like that? I think they scrapped the whole project :(

[AlphaChicken]

so have you embarked on a phase change cooling system ?

ALmost. Like I said it wasnt worth it to get all the tools for $3000 in order to build one $600 unit. I still know everything I learned about it though. Did tons of research, checked some books out from the library, talked to some HVAC engineers, etc. :D