Frost!

[Michael_C]

It has never idled above 30oC, must have been about 10 in my room when it was at 14.

[brad72]

Ok I know this topic has died out but I have a couple questions to see if this is possible.

First off I am a machinist which I do both manual and cnc machining. I was wondering if it would be possible to cut out a pocket below a heatsink and insert a peltier then press fit another copper plug snuggly against the peltier inside of the pocket on the heatsink. Plug would be about 3/8"-1/2" solid copper. I would cut 2 small reliefs in the heatsink so the wires of the peltier would hangout.

I am designing a couple heatsinks myself 1 of solid copper and one of solid aluminum with the copper plug. I am not using fins on this heatsink rather through holes as well as some angled through holes amongst the heatsink. With a vast majority of the heatink directly in the center being milled out leaving about 1/8"-1/4" of material in the center to contact with the Copper 3/8" plug.

I was wondering if that would be to thick or thick enough to prevent condensation from the pelt? May not even go with the pelt depending on the cooling ratio before milling out the pocket for the pelt.

I am making it so that either a 92mm fan can sit flush inside of the heatink or with a 120mm fan sitting on top of the heatsink.

I am about 1/2 way through several drafting designs in autocad when I complete I will post another topic for it.

Either way I am making 2 heatsinks as I said the copper one will be one solid piece and the aluminum will have a copper plug (not like a lot of heatsinks where they have a small 1/2" - 1" round plug about 1/4"-3/8" thick) My design is going to solid copper base 1 1/2" surface about 3/8" - 1/2" thick.

Another thing I am open for suggestions on is mounting ideas. I could cut out a section and put the spring type from either the old Thermalright SI-97 or even dismember a stock AMD heatsink and steal their lockdown mechanism, or 3rd I could mill out several tabs sticking out of the sides of the and place screws with a spring to mount through the motherboard.... Any ideas on this would be greatly appreciated....

[Blackima]

Oks, firstly the mounting. The best, most efficient form of DIY mounting I've seen is just making use of holes around your socket as shown here:

And then just cutting off the excess acryllic. Other people have used long metal screws with nuts on the back of motherboard

You don't actually need to go through the hassle of making the peltier fit neatly into the heatsink / copper plug. It looks very impressive, but doesn't really come with any benefits other than preventing ice forming around the peltier itself (which could be dangerous). Most people just sandwich the peltier between the copper plug and the heat remover and fill in the gap with sealant:

Now if you want the peltier to be poweful enough to cool the cpu, I'm afraid there WILL be condensation / frost. But don't worry too much about it, just accept that condensation will occur and follow the precautions neccesary to make sure that the condensation doesn't form on your cpu / motherboard. This is probably the best guide I've seen so far:

http://www.gruntville.com/howtos/peltier/index.php

Now onto the actual peltier part. You're not gonna like this but I strongly advise that you don't cool your peltier with an aircooled heatsink. I say this because the heatsink would need to dissipate at least 300W of heat if used on a peltier over a cpu. As it is the best heatsinks + fans on the market can jsut about manage 300W heat dissipation and the rate at which it removes heat falls as ambient temperature rises. So you'd also need to be taking at least 300W of heat out of the case as well (achievable with good circulation).

I'm not going to tell you not to try it, cause you might be able to make a good enough heatsink. But I do not recommend it. Water cooling is just about the best (and effortless) way of removing heat from the hot side of the peltier

What power peltier were you thinking of using? a 170w would be able to handle the heat from a cpu but wouldn't cool it much at all. A 230W+ one would do a much better job, but don't forget, the higher the peltier's power the more heat to remove from the hot side. How are you planning on powering the peltier?

Now if you want to use your machining skills to good use, Ive seen some really inspiring DIY jobs involving tecs and watercooling:

Dual pelt setup: http://xtremesystems.org/forums/showthread.php?t=57517

5 - peltier setup!! : http://www.xtremesystems.org/forums/showthread.php?t=64324

[brad72]

Very informative thank you...Also have an idea for a 2 piece heatsink with water channels through out and having it braized together so no leakage and having heatsink fins on the outer edges with a fan mounted on it with the intake being low near the bottom and having the exit being near the top of the heatsink. I drew up the plans today at work and will be working on the program to mill it out tomorrow. and hopefully be testing it over the weekend... If that works my company's owner already said he will personally file the copywrite under my name for me. As a part of my bonus. :o as well he said if it goes anywhere he wants a cut. ;) Just doing this to play around with some ideas but he thinks it is very interesting as he is also into computers and knows about water cooling but has never really seen any heatsinks with water channels just the actual water blocks....I was thinking with the water/heatsink it would sort of act like another radiator to sort of cool again before going to video cards....More on this with pictures on a new thread once I start the procedure and go through the various steps and stages....

[Blackima]

Heh, wow! Please do post pics, even just sketches. Must be great being able to actually make this stuff :)

The water channels should work, I think. Most good heatsinks these days uses "heat pipes" which are very similar to your idea, though they usually contain ethanol or mercury because apparently they do a better job than water.

All a heatpipe does is have a hollow copper tube containing water/ethanol/mercury (ie a liquid). When the bottom end is heated, the liquid changes phase to a gas (evaporates). This means that the heat energy is used to convert the liquid to gas rather than just heat it up. The pressure difference causes the gas to flow very quickly to the top of the heatpipe. There it condenses, releasing heat and thus warming up the top end. The result is heat is transfered incredibly quickly away from the bottom end to the top end, faster than a metal conducts.

I don't know how the water channels are going to help, so I'll be very interested to see the results :)

Go for it! Innovation's always a good thing.

(here's some simple diagrams / pics of heatpipes, dunno if it's of any use to you though :p. http://www.hsmarston.co.uk/heat_pipes_01.htm)

[brad72]

Well as most water blocks have an inlet and an outlet so will this heatsink. The intake will be near the base with the CPU the water then will wind through the channels to the top outlet thus cooling as it raises away from the CPU, and out the outlet onto the video cards....

Basically water from start point (reservoir & pump) through the radiator to the heatsink/radiator (what I am calling it for now) then to the video cards and recycles....

Same setup as a normal water cooled pc but instead of a normal water block in the CPU you would have the heatsink/radiator with or without fan to ones liking. Fan obviously would (hopefully) add a little greater cooling to the water system thus dropping the temps maybe another couple degrees. Also in hopes to maybe reduce the reservoir size and or existing or potentional radiators....

Thus for people not wanting such a bulky water cooling system or wanting to add extra cooling this might be a solution before having to go to A/C units..... Work in Progress obviously :D

[Blackima]

Oooh

Do post pics and stuff!

Really interested to see how this progresses :)

[Gargan]

I've been inspired to fianly upgrade my watercooling with a TEC. I think I'll order the parts tonight.

[Blackima]

I've been inspired to fianly upgrade my watercooling with a TEC. I think I'll order the parts tonight.

Heheh, brilliant! Do keep us update on it :)

That's a great setup as it it. Are the dual 7800's watercooled as well?

What power TEC (peltier) are you planning on using? Also how are you intending to power it?

[brad72]

Ok drawings programming are done for the new heatsink/radiator...sorry not going to post as of yet...but I will soon...going to wait a bit as others can go ahead and steal the ideas but don't want my drawings to be copied yet...hopefully the mill will open up at work this week so I can get started on this....the regular heatsink and fan idea I have been working on should be completed in the next couple days...mainly have deburring and polishing and adding some air holes down around the base of the unit left to do....

Basically normal heasink design although the top I have recessed a pocket for a 92mm fan to be inset into the heatsink or you can mount a 120mm to the top of the heatsink. Then it is solid aluminum with a cone shaped hole leading down to the copper plug to force the air directly onto the plug with air holes which are going to be angled down and out (not added yet around the base of the heatsink just above the plug) to blow cool air around the CPU itself instead of just onto the plug. Around the top of the heatsink are fins that are machined out but rather thick but I do believe even though they are a lot thicker than the thin fins that come with the aftermarket heatsinks now that with all the air being forced through the cone to the copper plug and out around the cpu before the heat rises to far it will already be cooled....I will post screen shots of regular temps with the Thermalright xp-90c and my design as well as pictures from various steps in making the heatsink when all is complete....

So please be patient and watch for the new thread probably in a about a week or so I will be out of town this coming weekend but hope to at least post temp shots by the weekend :D

[GrimReeper]

I have a question. If a phase change cooling system can produce sub zero CPU temps on its own would the Peltier hold the phase change cooler back or let it cool even better?

[brad72]

Question back for you....why would you want to add a peltier to a phase change system? You would not see any added benefits as first the peltier wouldn't get any colder than the phase change system but would add more heat on the opposite side of the cooler so with my knowledge there would be no benefit....as Phase Change is already producing sub-zero temps.

To answer you better I don't think it would hold it back but also don't think you would receive any benefits either....

[GrimReeper]

Question back for you....why would you want to add a peltier to a phase change system? You would not see any added benefits as first the peltier wouldn't get any colder than the phase change system but would add more heat on the opposite side of the cooler so with my knowledge there would be no benefit....as Phase Change is already producing sub-zero temps.

To answer you better I don't think it would hold it back but also don't think you would receive any benefits either....

Ok thanks, I didnt know if it would be a benefit, a hindrence or what. Now I know :D