Peltier Cooling

[DarKnightSP]

I have been researching about the Peltier effect for some time and I want to adapt it to cool a CPU. I know this is nothing new and it has been done lots of times but I alway see the same problems, power, condensation and cooling the hot side of the peltier. I want to start cooling a Dual Core CPU I had in my previous PC due to it doesn't have a very high TDP (65W) to work with. I would use a 72W TEC1-12706 because it's very cheap and exceeds the power of the CPU so I will be able to cool it. I don't want to go subzero, just below room temp in order to be easy to deal with condensation. So here are my thoughts about how to deal with this problems: 

 

- Power: The 300W power supply, as seen in the datasheet, is capable of delivering 10A in the 12V cable (I suppose molex conectors will be fine) so as the Peltier cell is 12V 6A it won't be a problem.

 

-Cooling the hot side: I will try with the stock Intel cooler but as I suppose that won't be enough I have the Thermalright Silver Arrow of my current build that I could use and should be more than enough.

 

-Condensation: My idea is to make a circuit that will turn on and off the peltier when the CPU reaches certain temperatures. As I said before, I don't need to go below zero Celsius, but below room temp (28-30ºC) and keep the CPU around 20ºC. For that I was planning to use a relay connected to one of the fan connectors of the motherboard and control it with speedfan to deliver very low voltage (I need to check with voltmeter) or 5V to activate the relay and then the Peltier. But I don't know if those connectors are DC or PWM and if they are PWM I don't think this will work (even if they are DC there is very low possibilities of this working).

 

So I need some advice in the part of reading the temperature and switching on-off the Peltier. The best would be not to use any external temperature probe because I think it would be very difficult to put it on the CPU.

 

Thanks for your help, and sorry for grammar mistakes as English is not my language.

 

 

[nmil]

You will need a lot more than the stock cooler to keep the Peltier cool, it's basic physics. If you use just the stock heat sink it will only be able to cool the CPU down the standard stock temperatures, now if we add more energy into the mix by pumping power into the Peltier, the heat sink will not be able to cope. @Stefan1024 did the sums and says that a peltier effectively triples the heat output of the component it's cooling.

[FilipSebik]

1 hour ago, nmil said:

You will need a lot more than the stock cooler to keep the Peltier cool, it's basic physics. If you use just the stock heat sink it will only be able to cool the CPU down the standard stock temperatures, now if we add more energy into the mix by pumping power into the Peltier, the heat sink will not be able to cope. @Stefan1024 did the sums and says that a peltier effectively triples the heat output of the component it's cooling.

Not true about tripling the heat output because i have tried myself and 190W heat sink cooled 100W peltier and 150W CPU to 0 `C

 

1 hour ago, DarKnightSP said:

-SNIP

You have to use CPU power connector or PCIe because molex is rated mostly 12V,B,B,5V and 1 Amp

[Dschijn]

It's just not worth the trouble...

[DarKnightSP]

29 minutes ago, Dschijn said:

It's just not worth the trouble...

I knew that before posting but I just want to make it only to see it running not to achieve optimal results in anything.

2 hours ago, FilipSebik said:

You have to use CPU power connector or PCIe because molex is rated mostly 12V,B,B,5V and 1 Amp

The datasheet on the PSU says 12V1 8A (YEL) and 12V2 13A (YEL/BLACK). The yellow and black cable is in the 4pin CPU connector and the yellow is only in molex, this PSU does not have any other connector rather than some molex, 4pin CPU, 20-4pin, and 1 sata. And the yellow cable of the molex is rated 20AWG with theorically admits 13.8A. So I think those 8A would go on the molex. The PSU is the FSP ATX-300PNR if you would like to check this. 

But, do you have any advice on how to do the temperature regulator using the inbuilt sensor on the motherboard and CPU? Buying one like this (link) would be easier to use but the problem is where to put such a big temp probe. Or can I use a termopar like this (link) with that thermostat. 

[lukart]

I would say get a AIO watercooling and get that to cool the hot side.

Then I would grease with Vaseline all over the place to keep air out of the CPU/Socket.

 

One thing, I wouldn't attempt to turn off the peltier, it would be too much temperature fluctuations too fast.

Just make sure there's no condensation and you'll be fine.

 

 

[FilipSebik]

1 hour ago, DarKnightSP said:

-SNIP-

Every PSU is different but the thermostat should work from ebay with that probe. But you should know its not difficult and You will spend most time trying to set the things than enjoying it. I spent 4 hours insulating my motherboard for nothing

 

 

Spoiler

[Stefan1024]

9 hours ago, DarKnightSP said:

- snip -

 

As a rule of thumb, the peltier should have about two times the power of the CPU. Also your peltier power regulation will be to slow to equalize the rapid changes of the CPU. Use a copper block between the CPU and peltier as a thermal buffer. And you need the big heat sink for the hot side.

 

8 hours ago, FilipSebik said:

Not true about tripling the heat output because i have tried myself and 190W heat sink cooled 100W peltier and 150W CPU to 0 `C

 

While running Prime 95 or idle?

[FilipSebik]

14 hours ago, Stefan1024 said:

As a rule of thumb, the peltier should have about two times the power of the CPU. Also your peltier power regulation will be to slow to equalize the rapid changes of the CPU. Use a copper block between the CPU and peltier as a thermal buffer. And you need the big heat sink for the hot side.

 

While running Prime 95 or idle?

Idel and prime 95 for 30 min was about 67`C but cooler was ultra hot. So good that peltier can handle 200`C because TEC12710 VIGAN

[Stefan1024]

11 hours ago, FilipSebik said:

Idel and prime 95 for 30 min was about 67`C but cooler was ultra hot. So good that peltier can handle 200`C because TEC12710 VIGAN

You can pump more energy througth the peltier, but then you have a negative delta T, meanige the side on the CPU is hotter than the one on the cooler.

 

 

And also this: