Proper mounting for a Peltier

[afd100]

After trying to get a peltier and HS to cool my PIII 733 under load (to no avail), I sent the unit back. My question is in what the company told me to do:

They suggest an aluminum shim between the PIII die and the peltier which spreads the heat over the entire surface of the peltier will help with the cooling problem (see thread 'Cooling PIII 733 and 73 deg C').

Is this possible? Should I be using a shim or slug between the peltier and PIII die, or has anyone been using a peltier on a PIII without the shim and seen no problems?

Thanks in advance for the help.

[Heavenly_abx]

Hi , I don't know who told you to use a "shim" between the cpu die and the peltier but it is totally wrong explaint to you !!
Here's how to setup a peltier, first you have to insulate the socket on your mobo with 'grade 2' silicone to prevent air going in and get condensation , then in the midlle of the socket you make a thin layer of silicone at the bottum and fill up the gap with closed cell foam.
On the backside of your mobo you have to insulate the part where you can see the soldering of the socket with closed cell foam because it can get very cold and again is a possible place to get condensation. Once you have insulate the socket and backside of the mobo whe start with the cpu. At the backside of the cpu you see some transistors in the midlle , put a thin layer of silicone over them so they are also insulated , To prevent condesation on the pins at your cpu you have to fill the socketholes with dieelecktrick grease (white vaseline will do also) Ok you have the socket and backside insulated , now put the cpu in the socket and try to make the edges of the cpu insulated by adding a very thin layer of silicone to the side of the cpu and the socket. To use a peltier you need a "coldplate" between the cpu and the peltier , a coldplate is usally a copper plate that has the same size as your peltier has , you MUST apply thermal grease (Artic silver if possible) between the cpu die and between the coldplate aswell between the coldplate and the peltier!!! Now you notice that if you stack up the colplate and the peltier that you have nothing to prevent air coming in touch with the coldplate /cpu/peltier , you can use closed cell foam around it , the closed cell foam may be a little higher (2/3 mm) as the top of the peltier after putting it all to your cpu , this will be a nice insulation when you put your haetsink in place and the clip will push it tight together! Use thermal grease between the heatsink and peltier if you put your heatsink on as last. If you take precautions like i described you will not have to worry about condensation. Just try to get everything as airtight as you can !! You MUST use a coldplate between the peltier and cpu die because the core of the cpu gets really hot and a coldplate spreads the heat over a greater surface so the peltier can cool it down and so also cools down your cpu. I use pelteirs for two years and have had no problems with condensation because i insulated it very very secure and did not hold back on the use of silicone. After installing one at the right way you will only have benefit of it !!
If this all has not scared you away from using a peltier then i wiss you good luck and if you have questions just post them and i help if i can!!

[rdmpe]

Excellent post! I think almost all of my peltier questions are answered! Of course, now I have new ones. When you refer to closed cell foam, I'm not sure what you mean. Like a thin sheet of foam padding such as what is sometimes used as shipping padding, ~1/4" thick?

[Heavenly_abx]

Hi thanks for the compliment!
Closed cell foam is a foam wich is air tight , the cheap mouse pads are also made of it.You can check if it is closed cell foam by trying to blow air trouhg it , if you cant then it is good enough to use with a peltier. i now there are some site's that sell it with a sticky(sorry dont now the right word)side side so you can place it where you want with out using some kind of glue.

[afd100]

Thank you very much for the GREAT post about peltiers. The only question I have is How thick should the copper coldplate be? Because of the Heat Sink clip, I don't think I could fit much more between the HS and CPU Die. Is there a practical thickness to use?

Thanks again for the GREAT peltier usage post.

[Heavenly_abx]

hi . the coldplate is usual 3mm thick , what kind of heatsink are you plannig to use with the peltier? i have to point out that you have to use a good quallity heatsink like the PEP66T from alpha or one that is having the same capability of cooling!! It may look like the clip is getting on to tight but if you use the same heatsink i do than it's just important to attach it with great care!! use a needle nose plyer(hope this is good english otherwise it doesn't make any sence !) and put some tape under the socket sludge so if you slip then you wont scratch the mobo! Put the mobo on something soft and flat so you dont bent the mobo to much wich could couse cracking traces inside the mobo.Again a tight fit is good as long as youre carefull. I dont take any responsebility if things go wrong !! I only point out how it is supposed to be done and there are no guarrantees ! Good luck !!

[jian]

Heavenly:

What are your temps at idle and full load?

[Heavenly_abx]

Hi , The temps are: idle 3 degrees celsius and 20 c under full load.

[jian]

Heavenly, those temps are great.

Mine is currently 34c and 15c using an 85watt (i think) pep66 and a delta fan.

I'm running 6 x 152 with 1.95volts.

I used to get the same temps as you when I had the same chip on a bx mobo (with a 72 watt). Can you give me more details on what voltage you're running at and more importantly, how exactly your pep66 is fitted?

I think this is the cause of my high temps.

Also, how did you manage to get two fans onto your pep?

Thanks.

[Heavenly_abx]

hi Jian , I removed the shroud on the PEP66T and mounted one delta onto it blowing towards the mobo. I have that fan raised a little away from the shroud using some spacers (plastic screws wich you use to mount your mobo to the case ) Because i raised the fan that bloaws towards the mobo i created space to at another delta fan UNDER the PEP66T blowing into the heatsink also but this one is blowing straight up towards the top of the case. I can use the one blowing up because i created room on the bottem by raising the first one that's blowing towards the mobo , if you don't raise that one then you can't place one at the bottum because the big transistors are in the way. i closed all openings by cutting some strips of aluminium and fitted them on the PEP66T , i let the top of the PEP open and there air exhaust from both the delta,s. I also have a 120mm fan on the sidepanel blowing to the PEP and the motherboard. If this doesn't make it clear (wich i can understand) then i can draw a model and mail it to you !
The Delta fans are runnning at 7 volts because my cpu desk sounded like a runway at a airport!!
Also make sure that you have enough fresh air circulating in your case by adding front intake and topback exhaust fans. Your temps are a bit on the high side for a peltier system , the PEP66T is a good heatsink but feel it sometime when your sys is on for a while and have done some work and is on idle , you will notice that it is still very hot at the base , it is capable of cooling a peltier but when overclocked a bit and upped the vcore it doesn,t have the capacityof cooling it for 100%. I am now adapting a Alpha heatsink (p3125) wich was for the slot 1 versions to fit the cusl2-c , i only have to cut of a little bit of one corner to clear the transistors , this heatsink has a bigger amount of cooling surface and a bigger copper inlay at the bottum.
Let you now how it works when it is done !!
btw , i am running at 1100 mhz with 1.80 vcore
idle =3c
full load= 20 c
I have bent the clip wich holds the PEP more so it is holding real tight to the socket.
Good luck !

[jian]

Thanks Heavenly, but i think i might need that diagram of you!

I think i understand what you're saying except for the part about the second delta fan bit.

i think my high vcore has something to do with my high temps. I have the delta fan blowing down onto the mobo and 5 case fans but only three sweitched on at the moment.

[Heavenly_abx]

hi, Jian , It's difficult to explain in english how i put on the second fan.!! I could draw it in bmp format and mail it to you if you want that? if yes then mail me your adress and i will draw a diagram for you , it really helped me gettin the temps down on another board i run without a peltier.

[Asha_abx]

Hello,

I don't now anything about peltiers, ... ehh although after your post Heavenly ...

Anyway I thought that peltiers were supposed to be cooled by watercooling, if I understand you correctly a simple heatsink/fan is enough to cool the hot side of a 80w peltier?

thanks in advance
asha

[Heavenly_abx]

hi Asha , Yea sure you can use a peltier with forced aircooling , the peltier with watercooling is done to get subzero temps (minus 6/10 celsius) or to eliminate fan noise. with watercoling the only fans that you use are the two that cools the radiator. I can imagine that the noise is getting people to watercool their sys , on the other hand , i use air and if you use it wisely noise doesn't have to be so loud . For now i don't need subzero temps so i gues ill stay with air for a while. I have bought a house wich should be ready in two months and then i have to do my setup from scratch , then i think i will start with water!! Plain air works greats do !!! Good luck!!

[jian]

Thanks Heavenly, but i think i know what my roblem is.

When my tower is on its side, the max temp at full load is 25c, (not too bad considering that I am running 1.95v). But when I stand it up, the temp jumps by 4c! The reason, when the case is vertical, the hot air from my geforce is rising into the path of my delta.

Also, I have managed to reduce the max temp from 34c to 30 at full load. I was using an extension lead from one of my psu molex connectors to the peltier connector, the connector must have been faulty becasue it caused my peltier to give up today. it didn't damage it but there are light burn marks on the connector! Removed the extension and the peltier still works.