PIII 700E with Peltier Cooler

[Jefferson_One]

I bought this CPU from a friend for $40, plus a PIII 450. This was a great upgrade for me, and still is, but I was hoping to overclock this chip.

I can, up to about 800Mhz - but the chip temp. runs about 53 degrees C @ 700Mhz. I know that is WAY too much, but it's a stock everything.

I have looked at the Peltier, and feel like it was not done properly. It comes apart really easy, and I noticed that the PIII 700 has a very small 'rise' in the center. That's the only place to make heat transfer. I need more paste on that, for one thing.

Also, there is a huge gap surrounding the whole chip -- air. I think this Peltier is smothering the chip, causing for such high temps. Case temp is about 32 degrees C.

What can I do? Everything is stable, and I can't believe this this runs at 50+ degrees C!! It has been for over a year now.

I want to re-do this Peltier setup properly. What should I buy (paste, etc.) to do this cooler right?

Thanks

Jeff

[FrankMasterFlash]

Welcome to the Forums º¿º
Yes, buy paste, Arctic Silver is the best and runs for about $8. Radio Shack has decent stuff for about $1.99. I recommend getting a Non-Conductive shim to make the Peliter level one the core. Make sure you have good case air flow to remove the heat from the Peltier.

First a few questions...

Is it Slot 1 or FCPGA?
What kind of cooling you using to remove the heat from the Peliter and CPU?
What wattage is the Peliter?

[Jefferson_One]

Thanks for the post ...

I have Abit BE6, 100Mhz FSB, cheap mem ... I mean, I paid $250 for 64meg, so thatwas a long time ago. Got 196Mhz total right now. The chip is a slot1 ... it's the peltier on there, with the original peltier fan. It's probably the cheapest peltier out there, I have no idea since I bought this used.

I have a fan drawing in, power-supply fan out, and a 3Dcool slot-fan out. Case temp is 32C with chip temp at 54C.

I've had this chip combo for about 7 months. I bet it's been running @ 54C for over a year now. Very stable still, and I can even go up to 800Mhz too. If I can get the peltier right, I should be well below case temp, and go pretty high. I'd think it's been 'burned in' long enough :)

So, I'm going to lap the CPU this week: what size paper grit?

Get some thermal compound ... what about sealing around the chip? I read something about that, but I can't find it. What should I use for that?

Jeff

[FrankMasterFlash]

Jefferson_One (Jun 23, 2001 11:10 p.m.):
Thanks for the post ...

I have Abit BE6, 100Mhz FSB, cheap mem ... I mean, I paid $250 for 64meg, so thatwas a long time ago. Got 196Mhz total right now. The chip is a slot1 ... it's the peltier on there, with the original peltier fan. It's probably the cheapest peltier out there, I have no idea since I bought this used.

I have a fan drawing in, power-supply fan out, and a 3Dcool slot-fan out. Case temp is 32C with chip temp at 54C.

I've had this chip combo for about 7 months. I bet it's been running @ 54C for over a year now. Very stable still, and I can even go up to 800Mhz too. If I can get the peltier right, I should be well below case temp, and go pretty high. I'd think it's been 'burned in' long enough :)

So, I'm going to lap the CPU this week: what size paper grit?

Get some thermal compound ... what about sealing around the chip? I read something about that, but I can't find it. What should I use for that?

Jeff

Do not lap the CPU at all!!! If you do it will just have look for a new chip because you will kill it. I did lap a Celeron 600 with the same type of core you have and killed it. I think Slake did that too and killed it. Plus, they come out of the factory pretty flat and thermal paste will fill in any of the micro gaps

I don't know anything about sealing the chip, but ask around in the cooling section and someone is bound to know about it.

Stock cooling is not good enough to get heat from the peliter and the CPU off. I recommend getting a Global Win VOS32(~$30) or a Alpha P3125(~$45)or a Swiftech. Or for the best go with a Water/Peltier setup.
See if you can get a little better case flow.
Is the chip at Idle at 54ºC or under Full load?

[bdf24]

Are you sure you don't have the words Heatsink and Peltier mixed up? There is no such thing really as a peltier fan? Heatsink fan or alot of people refer to it as HSF. is it a aluminum base with fins coming out? If so that is a Heatsink, not a peltier. A peltier is usually 40mm x 40mm and is about an 1\8" thick. Like to small ceramic tiles glued together.

Sorry if I'm coming off as treating you like a newbie. I'm just a little confused about what you posted.

[Jefferson_One]

bdf24 (Jun 23, 2001 11:50 p.m.):


Sorry if I'm coming off as treating you like a newbie. I'm just a little confused about what you posted.

I was thinking they were allclose to the same: peltier with heatsink & fan. Anyway ...

Around the peltier element, I *think* there is supposed to be some foam type sealant around it. I do know the difference, lol. I doesn't bother me in the least to strip down a system and reformat too ... I'm a tweaker :)

This chip has been running stable - at idle - at 54 degrees C. I'm not real sure on a 'full-load'. I'll check that tonight. I know I can get 800Mhz out of it, even with the extreme heat.

I am using the standard issued Abit thermal lead for readings. The lead has been checked for accuracy, and it does in fact read correctly. I'm sort of shocked that the chip has been running at such a temperature!

Okay, so I won't lap the CPU. I got away with that on my celery 366 o/c 500 just fine, but I agree, it's probably not needed.

I *think* the biggest headache to peltier coolers, is the fact of "sealing" the CPU ... I wanted to hear what you guys thought. Mine is *not* sealed, and the element and heatsink are smothering the CPU.

Jeff

[Jefferson_One]

I just ran 3DMark 2001 demo ... the temperature never budged. It's still at 54C, as reported by MBM5.

What *should* be an idle temp. for a PIII 700?

Jeff

[Flu!d]

I'm having trouble understanding your post. But if your pIII is running at 54 degrees C using a peltier then your peltier isnt working too well, my PIII (spec below) is running at a max of 35 degrees C and i'm not even using any elaborate cooling, my PIII667 @ 750 also ran at a max of 35 degrees C using a golden orb!! Either you need to draw the heat away from your peltier better before it kills your chip or remove the peltier alltogether - your system will run cooler provided your heatsink is installed right and you use a little common sense....
Stay cool fellow Intel user!

[bdf24]

I guess it would help if we knew what size tec you had on there. Also as far as smothering you cpu. Thats what it has to do. Is there a cold plate in between the cpu and tec? Also yes you need a monster HSF to dissipate all the heat being created by the tec. As far as sealing it off. it depends on how big the tec is and how much power your giving it. if your only giving it 12v's then say its a 50w tec. thats not gonna run cold enough to need to seal it off from my experiences. 72w tec and higher then you'll need to. So you dont get any condensation. But in your case something's not working right!

I would suggest just taking the tec off and running the HSF alone. I'll bet your temps drop!

[Jefferson_One]

I was thinking the same thing: if I remove the current setup, and just a HSF, then the temp. would go to about 35C. That's my prediction.

I have a basic peltier setup: bought used from a friend, I do not know how it was installed, but it does not look complete to me. I do not have any specs on the device, and I could not see any manufacturer. It basically is, the peltier plate with positive & negative wires, with a large golden-foiled heat sink, with a standard fan mounted on top of that.

Things *look* right - I can't see anything that looks bad, except for the possibility of the sealing. I can't tell what wattage the peltier is, but I bet it's not much.

Jeff

[bdf24]

Is there any aluminum or copper plate between the cpu and the peltier? There should be. Also to me it sounds like its not even working or the HSF just can't deal with the heat. You said it comes apart earlier? You may need to reaply some thermal compound and tighten it all up. But make sure you dont put the hot side of the tec on the cpu! Believe it or not I have done that. Luckily it didnt fry my chip. The system just would not post.

[Flu!d]

Adding peltiers to computer cooling systems is like turbocharging cars....You can't just slap any old turbo on and expect it to work in harmony....Although you might get lucky there are many variables to consider. The other thing is that you have to remove the heat being transferred by the peltier faster then the peltier is 'transfering' it, otherwise it's just gonna keep getting hotter. While PIII's can be pushed to the limits of the P6 core using peltiers I really don't think they're nessecary on PIII's, I think you'll achieve a nice overclock without it....Especially if it's runing at 55 degrees C!

[Jefferson_One]

I probably never would have bought a peltier ... it sort of came with the deal, so, I might as well put it to use.

I checked it out again tonight - looks to me, like the ceramic/white side is on the chip, and a separate thin metal plate is sandwiched between the tec and the heatsink. My guess is, they got it backwards.

The whole assembly comes off quite easily, but is locked sturdy into place. It seems there needs to be a little more thermal compound from the chip side, and the thin metal plate seems to be semented to the heatsink. If that's the cold side, then I can't really get that off.

Actually, when I removed the chip from the peltier, the side the was touching the chip was hot. I mean, there is a LOT of heat around the chip as it is running. It seems like the fan is blowing hot air onto the chip.

Does the metal plate of the peltier touch the chip, or the heatsink? Is it removable? Does the fan blow towards the chip, or away from?

At least is it is still running, even at base 700Mhz. Right now, the chip is at 49C and the case is 28C. What should the nominal temp at idle for the 700E?

Thanks guys ...

Jeff

[Flu!d]

My PIII (spec below) idles at about room temp.....Right now surfing the net it's at 23 degrees C. Your chip should be at about half of what it's at now, 50+ degrees really is getting on the high side....Is the system stable (totally stable)?

[bdf24]

Flu!d

In some cases pelts can help quite a bit. I have a PIII 800E. Without a tec on it I cannot run over 960mhz stable. But with a tec installed I can get it to run at 1008mhz 100% stable. I know the difference from 960mhz to 1008mhz is'nt all that great. But hitting the 1gig mark is very important to a lot of people. And using a tec is what did it for me.

[qc]

I have the same problem - 30 C idle, 50+ C on load with my PIII 700E + Golden Orb + 2 X 80mm case fans+ fans on chipset and video card

[Flu!d]

Bdf24,

If you take a close look at my post you will see that I mentioned how peltiers can be useful in pushing the P6 core to the limits, I mentioned this because I remembered the results of your experimentation with peltiers, so I do agree with what you say....Although peltiers can be dangerous in the hands of the unexperienced....You think AMD's run hot, their temps are nothing compared to a PIII (or any chip for that matter) with an incorrectly installed peltier.

Be careful and stay cool people!

By the way Bdf24 - cute kids! My girlfriend and I have only got a kitten, but he's my baby!

[bdf24]

Flu!d (Jun 26, 2001 02:33 a.m.):
Bdf24,

If you take a close look at my post you will see that I mentioned how peltiers can be useful in pushing the P6 core to the limits, I mentioned this because I remembered the results of your experimentation with peltiers, so I do agree with what you say....Although peltiers can be dangerous in the hands of the unexperienced....You think AMD's run hot, their temps are nothing compared to a PIII (or any chip for that matter) with an incorrectly installed peltier.

I totally agree with what you say! Pelts are very dangerous in the hands of the unexperienced!

And Thanks for the compliments on the kids. Those two are my pride and joy. I also have another one on the way!

Be careful and stay cool people!

By the way Bdf24 - cute kids! My girlfriend and I have only got a kitten, but he's my baby!

[Jefferson_One]

Thanks for the comments ... I pulled the whole thing off again. Verified the cold side was in fact on the core; cleaned core & peltier of residue, and re-applied themal compound; following a tip, bought foam sealer and applied thin coat to seal around CPU core; used volt/ohm meter to check peltier element ...

... and - still sitting at 50C :( I am now overclocked to 800, but seems like I could get better than that. The Abit BIOS reads the same as MBM5 ... but Sandra says the CPU temp is 30C! Which should I believe??

Jeff

[vimal]

This sounds awfully familiar - actually, this is exactly what happened to me with my PIII-750.

Quick diagram of what you need (not to scale, and I am not an artist):

||||||||||||||||||||||||||||||||| <- heatsink (preferably a large one)
~~~~~~~~~~~ <- layer of thermal paste ( I use silicon paste)
[][][][][][][][][][][][] <- peltier chip (make sure hot side up)
~~~~~~~~~~~ <- another layer of thermal paste
=========== <- cold plate - a piece of aluminum (1/8"-1/4" thick)
~~~ <- yet another layer of thermal paste
____###____ <- processor

I had two problems, both of which produced the same symptoms you have.

First problem: I didn't use a cold plate - very bad idea. The small area of the peltier directly touching the core will get hot, while the rest of the peltier will remain cold. Not what you want. I used the lid from one of those small plastic project boxes you can get at Radio Shack as my cold plate (it is a bit on the thin side though)

Second problem: I didn't have a big enough heatsink and fan. A peltier does not generate coolness. It merely creates a difference in temperature from one side to the other. If you let the hot side get too hot, than the cold side will start to get hot too. I have found that if you can comfortably touch the heatsink while it is in operation (yes, it will be hot, so be careful) then it should be okay. If not, get a bigger heatsink of a bigger fan. (I stick a 4" case fan next to mine - reminds me of a turboprop)

Oh yeah, the foam insulation around the cold plate is a good idea, especially when the processor is idle/low stress. I put my insulation on afterward, just to make sure it doesn't get in the way of the important contacts.

Good luck,
Vimal

PS: Trust what the BIOS and MBM say - always better to err on the side of caution

[Jefferson_One]

Thanks Vimal, for the illustration.

In my Abit BE6 BIOS, I can read a "system" temperature (tho I don't know exactly what that is reading), and it stays around 33C all the time.

Also, I can read CON2 for the external thermal lead ... that's the only way the BE6 can tell CPU temperature. Unfortunately, I have broke the leads and will need to get a new one soon.

As for the peltier design, here is a picture (minus wireing) of what I have:

http://www.a-pro.com/Access/FANAC3P-G.JPG

What you see on the underside of the pic, is the cold side of the peltier ... I tested it, and it get cold! Minus temps. I do not have any plate to go on that side. It came pre-assembled out of the box (a friend installed it), but I'm thinking he might have left off the aluminum/copper plate????

Basically, from the pic, take the CPU and couple it right to it ... that's how it is now. I think the spot the CPU makes contact is getting hot, while the rest of the element is cold. There is a lot of heat flowing around in the genneral area around the chip.

I use a tip and bought some Great Stuff foam, and put a thin seal around the perimeter of the core, hoping that might help. It didn;t change anything.

Yes, eveything is very stable running 700Mhz @ 1.65V/55C. I can overclock to 800Mhz @ 1.65V, and depending on the placement of the thermal lead, about 55C - 60C (measuring the ambient temperature around the core).

So, I will get a new thermal lead soon (heard BE6 deos not monitor diode) and should I get a plate from Radio Shack or something? It'd be no problem to install it.

Please advise on what type of plate I might need, and how to install.

The whole peltier device (see pic) is pre-assembled. Hot side seems to have a metal plate to the HSF, and the cold side can be checked, and it works perfectly. There is something now right somewhere, but I'm not sure where.

Thanks for the help guys!!

Jeff

[vimal]

From the picture link in the above post, looks like you are definately missing the cold plate. Look for a thin piece of aluminum (workable) or copper (preferred) that is at least the size of the peltier element. It should be thick enough to be rigid (1/8" is good, 1/4" is better from what I hear)

Link to crazypc which is selling a reasonably cheap copper plate. Unless you are very impatient (like me) and HAVE to get your cold plate now, I say buy this one ($6+shipping):

http://www.crazypc.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=120199&Product_Code=5915

If you are impatient, hop over to the local radio shack, and look for those blue plastic project boxes (something like 2"x2"x4" or thereabouts) Though these cases are plastic, they come with a spare aluminum cover and will only run you something like $3 for an appropriately sized one.

Once you get a cold plate, just sandwich it between the CPU and the heatsink/peltier combo with thermal grease where appropriate.

When sandwiching the cold plate, make sure it is resting flat on top of the core. I had to trim my plate cause one corner would rest on the raised plastic part of the socket, lifting the center off the core.

-Vimal
_________________
PIII-750@930
2xPIII-550@617
Celeron 366@458
K6-2 266@337
Cheap Wallet@$0.00

[Jefferson_One]

Thanks again!

I took your advise, and went to Radio Shack and got the box with plate. It's aluminum, but I snipped it to fit, and coupled it to the element.

I have to take another look at my thermal sensor, I think it is broke now - too much flexing. I will try to solder it today - no stores around here have those thermal leads.

I got it all put back together, but I can't monitor the CPU temp right now.

I wonder about the stepping .... is there a know stepping for the 700E that is NOT very overclockable? I was thinking I could get another 700E for about $140, then go into some case mods with a dremel tool! That's my next project I guess - hehehe

Thanks again ..

Jeff

[DAppel]

Your problem really seems to be contact surface. Don't forget that aluminum bends easily, so whenever you attach the cooler to the chip it may be bending slightly (even the peltier) and creating a small gap at the center of the core. In this case, the peltier is saving your CPU, because the temp differential it creates is so big that it manages to keep it at 50C by only contacting it at the corners (heat travels).
(Someone warn me if I'm talking BS.)


Regarding FrankMasterFlash's reply (way above) about not lapping it, I've lapped mine (600 grit) and never had problems with it. Not something really worth doing (got only 2C lower at peak), but possible. You only need a (very) steady hand.

I would do it again. 2C is always better than nothing.

[vimal]

If with the cold plate you still can't break 800, then I would have to agree with the above post that contact is the next thing you have to worry about.

Flatness is very important. Look carefully at the aluminum plate from the side. Make sure while you were snipping it, nothing got bent (even slightly - aluminum has a nasty tendency to curve or mash up at cut corners) Also, try to make sure the plate isn't curved at all.

To check for how well the cold plate is contacting the processor, you can do the following:

1. Clean off any heatsink paste on the bottom of the cold plate and the top of the CPU core. A small amount of rubbing alcohol on a soft tissue may help.
2. Take a very small amount of heatsink paste, and dab it on the center of the CPU core.
3. Spread the heatsink paste using a thin flat surface. I use the edge of a razor blade (be gentle, do not want to scratch the core) Spread it out as much as possible.
4. Very gently, scrape off most of the heatsink paste.
5. Mount your coldplate/peltier/heatsink assembly, and then carefully remove it (don't let it slide from side to side)
6. Look at the bottom of the cold plate. If you see heatsink paste in a relatively even rectangular area, you are good. If there are spots within that rectangular area that have no paste residue, then you have problems. Possible solutions include using more heatsink paste and sanding/lapping.



Oh yeah, another crazy (as in take it with a grain of salt) thought:
Go to intel.com and look for the spec sheet on the PIII processor. It should tell you which two pins correspond to the thermal diode for the PIII. Try to find where those pins are connected to on your motherboard/slocket. Then pull out your handy-dandy multimeter (if you don't have a multimeter, stop buying computer stuff and save up for a good one - you will be happier in the end), and measure the resistance across those two pins. (It is important to note the direction) I'm sure somewhere in intel's vast database of stuff, there is a table which will convert that resistance into an approximate temperature reading. If you do this, you can use the internal PIII temp sensor (which, while not always accurate in absolute temperature, will give you a great idea of what is actually going on at the CPU core)

[Shadow ÒÓ]

Moved post to Cooling.