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Hardware

Extreme CPU Cooling 80

Posted by CmdrTaco from the I-promise-not-to-make-a-cool-pun dept.
Darkfell writes "Check out todays HardOCP. An article was posted by a guy who cooled a dual PIII down to -59.7C. Very nice setup." This is worth a read- quite detailed for you do-it-yourselfers willing to risk destroying your computer.
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Extreme CPU Cooling More

Extreme CPU Cooling

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  • Too cold? (Score:1)

    by Anonymous Coward
    moving electrons create friction,

    I guess you would have to leave that cooler on in some way as the expansion and contaction of the silicon and metals and glass cant be too qui9ck else a crack... A timer for cool down and heatup...

  • I don't think it's quite THAT dangerous (Score:1)

    by Anonymous Coward
    As both a surgeon and someone who's used liquid nitrogen a lot (for cryopreserving cells for tissue culture), I think you're overestimating the danger. Liquid nitrogen is something like -192 C, and I've gotten drops on my skin a lot of times - it stings a bit, but isn't any worse than getting spattered with grease drops while cooking.

    Also, it takes quite a while for thermal damage to involve anything deeper than the skin. Even people trapped in burning cars or buildings essentially never have burn damage to underlying fat or muscle (unless they die and remain in a fire for an hour or so).

    Getting splashed with -80 freon could probably damage your eyes pretty rapidly, but it wouldn't kill you unless you immersed your head in it for some time.
  • Posted by Mike@ABC:

    Sure, speed is great. But this? You just gotta shake your head and ask "why?"

  • I've read somewhere that those puppies work faster when you cool them down!

    If they replace the current design locked on an external clock, what they probably will do eventually, I think overclocking is gonna take a completely new dimension. Of course it's not gonna be overclocking as such, it's gonna be more of a Mr deep freeze built from bits and bobs in the back of your garage...

    much fun for the next (hopefully?) generation ;-)

    ---

  • >You just gotta shake your head and ask "why?"

    What's that quote again? "Never ask a hacker why, just smile and slowly back away" or something very similar.
  • That guy is obviously bored ! Then again, it is quite an impressive setup.
  • It's basically the same concepts with engines. The more heat created, the less efficient it is. Heat == inefficiency. Granted, engine heat comes from friction, and. um. stuff. but. um. yeah. *considers there aren't moving parts in chips* something like that.


    Me.
  • Can semiconductors even operator correctly at that temperature?

    "In true sound..." -Agents of Good Root
  • I can't help but remark on your sig. It is illogical - because, if the only humans are cannibals, then who are they eating? :)
  • I would suggest being very (very) careful with your pipefitting & pressure testing, and thinking about what kind of containment you have in place. There is clearly enough thermal energy (actually, lack of thermal energy) in that reservior to kill you in a few hundredths of a second if you get a faceful of it.

    It appears that the author of the article either knew what he was doing, or took the time to figure out what he didn't know and learn it in great detail. Be sure to do the same if you try something like this yourself.

    sPh
  • Not my business, really. But you might want to look a little more closely at the details. He used 1.2 q of water/glycol as the heat transfer medium. A drop of liquid nitrogen is one thing; a quart of glycol at -50C is another.

    Of couse, accidents always happen to the other guy, so there really is nothing to worry about :-(.

    sPh
  • This news can be considered more hardware news...but /. needs to have more hardware news for the do-it-yourself-with-linux puppies.

    Rob, do you get enuff material on h/w news?

    CP
  • I read about laser cooling few year ago in a magazine. This cooling device have no moving parts and I think it is efficience too. I really like to have this wonderful device.
  • That's an awesome idea. :-) Unfortunately, it comes with a built in heater (the dual PIII's).

    Sujal

  • Check out Tom's Hardware [tomshardware.com] he just put up an article [tomshardware.com] on his work with a Kryotech case and a Celeron 400.

    Had the beastie running looped Timedemo1 for a straight WEEK!


    Chas - The one, the only.
    THANK GOD!!!

  • I've been thinking about doing this for a while, and I just may do it now.

    All ya gotta do to cool your pc down (granted not to the -8billion that these guys do) would be to pick up an old auto-defrosting fridge that nobody wants anymore, cut or otherwise remove the barrier between the freezer and the refrigerator compartment (just to get it that much cooler), Take the door off (or leave it on and do what I'm going to say next if you want to get really fancy) and put a piece of insulating foamboard up where the door was.

    Take the covers off of your case(s) and put them in the fridge. Cut holes where the floppy/cdrom/etc will be so you can still get to them. cut a corner out of the foam board to run power in/kbd etc out.

    Done. A cooled system. (or an array of cooled systems :)

    Just dont try and use the non-autodefrosting fridge unless you dont like your computer(s).

    I think when I get back home I'll start looking for a used fridge :)

    ---------------------------------------
    The art of flying is throwing yourself at the ground...
    ... and missing.
  • Thats why you would need to use the frost free/auto-defrost fridge.... to keep the humidity down.

    just dont open the door too long and let nice humid air hit a 32F case :)
    ---------------------------------------
    The art of flying is throwing yourself at the ground...
    ... and missing.
  • Unfortunately not. We won't have one up for another week. We ran some testing with our cooling apparatus.. two tests failed (one with spectacular results!), but we did cool the system down, albeit with lots of hissing from evaporating dry ice. We later discovered we could make it more effective if we *didn't* have air running over the dry ice. :/ Stupid. I should have known that.

    Anyway, I fried an AMD K6-350 (my fault) by not resetting the jumpers from 3.5 to 2.2v. The new one will arrive today. I'll have a webpage up within a week. Slashdot may post it. Or maybe not. We'll see. I'll e-mail you once I get everything back into shape. ;^)


    --
  • We've done it using dry ice. The chip dropped temp to around -100C. It ran perfectly. We managed to take a P120/60MHz bus => P200/100Mhz bus. Stable.


    It can be done. We've done it. Thermal contraction is only an issue if you cool it *too quickly* - we're looking into nitrogen for the next test. Passive submersion - the whole board. Should be interesting. But to answer your question again - thermal contraction until about -100C is a joke - don't worry about it. Much.





    --
  • This could lead to a new product!!! Imagine it's marketing potencial!!!
    The one and only, MULTIMEDIA FRIDGE!!!
    Yes, you can work and have cold soda, sandwichs, yesterday's pizza and beer, at the reach of your hand!
  • I wonder how long it will be until we start seeing a mass trend towards cooling systems being incorporated into cases? It will probably be server cases at first of course but anything that starts off with a hobbyist in a garage saying 'Hey ! .. Look what a good thing this does!' is bound to increase awareness of it among the chip, m/b and case manufacturers.

    A good comment on another page of www.hardocp.com talking about the 'SupaChilla' prototype saying

    the SupaChillä gives you the option to beat the performance curve, you've got tomorrow's CPU power today


    Maybe that's the way to go along with simply increasing the clock speed.. Either that or use more power efficient processors in the first place.. can you say StrongARM?
  • I tried this, using very small copper tubing. It is VERY IMPORTANT that you find out what the DEW POINT is and not cool below it! You'll condense water on your motherboard, as I did. If you live in a humid climate or a dry climate with a swamp cooler, you must be very careful!


    The author of the article took care to insulate everything, including the pipes, to prevent this from happening. Look carefully at the pictures of the finished system and you'll see the insulation.

  • I just cant wait till someone get's upto date w/ x86 structure.. Full 128 bit x86 would be nice..


    Full 64-bit would be nice, even. However, even 32-bit is a kludge with the way it's currently implemented.


    The floating-point/MMX registers on an x86 are 64-bit. I'm not sure how wide the SSE registers are, but I'd guess 128 off-hand. The general-purpose registers have been 32-bit since the 386, and are accessed using a hack on top of the old 16-bit access method (put 0x66 before the opcode for your instruction to make it work on 32-bit operands instead of 16-bit).


    There are many fixes that could be made to the x86 register set and instruction set, but the best fix of all would be a complete redesign to a new system. However, Intel can't do that without breaking compatibility with its established software base. Breaking compatibility would leave them at a disadvantage to people like Apple, who already have a more cleanly designed processor with an installed software base. What they're actually doing is hedging their bets and giving the Merced the ability to emulate x86 operating modes. However, this will be done at the cost of either more silicon on the Merced, a slower chip, or both.


    I use x86 machines, and for the time being they're competative performance-wise, but it's just a matter of time before the architecture runs into the ground, because it's a mess of patches on top of patches that wasn't built to be extensible. Intel's best bet is to phase out x86 support once there's a significant amount of Merced-native software available. Whether it succeeds in competing with the G4 and whatever Sun, DEC^H^H^HCompaq, and others offer remains to be seen. HP seems less than enthusiastic about it, and they helped Intel design the thing.

  • This is a very impressive setup. The authour took the time to do proper research and put in the effort to build a cooling system that was structurally sound and reliable.


    He'll run into problems when he tries to reach -80, though. Sooner or later traces in the chips or on the chip modules will crack due to differing rates of thermal expansion in the materials used. An interesting read nonetheless, though.

  • Can semiconductors even operator correctly at that temperature?


    Yes. In fact, they operate more efficiently, which is why he could boost the clock rate. This is also why processors fail at higher temperatures; they work _less_ well as the temperature increases. If I understand correctly the transistor threshold voltage and a few other parameters vary with temperature. I'd have to dig out my old electronics textbook to give you a detailed explanation, but the gist of it is that the transistors end up passing more current, which decreases switching time.


    Limits to clocking with this kind of scheme are chip failure due to electromigration (the traces in the chip can only take so much current), and chip or module failure due to cracking caused by different rates of thermal expansion in the materials used.

  • I have move up to Anhydrous Ammonia (R-717) in order to achieve sub -100C. Standard CMOS devices today can operate in -120C to -150C without problems but can be clock at twice the speed that is safe at 50C. Improvements in the "doping" process at a relatively cheap cost will allow further cooling to sub -150C and at -202C you are restricted by the quality of the PLC and not the processor. 1.6GHZ would be the theshold of the crystal today.


    This doesn't address the problems that I raised - thermal expansion/contraction difficulties and electromigration. While you do mention the limits imposed by the way the threshold voltage changes with temperature, the other two factors mentioned may be what limits your ability to cool and overclock chips.


    An integrated circuit chip is a chunk of silicon with aluminum wires on top of it embedded in a thick layer of silicon dioxide. These three materials have different coefficients of thermal expansion. As you cool them, they will change sizes at different rates, causing stress in the chip. Cool them enough, and your chip will break. I'm told that the temperature at which this occurs is lower that I had originally assumed, but it *will* happen. Possibly with liquid nitrogen (though some successful liquid-nitrogen-cooled systems have been built), and almost certainly if you do something silly like cool a chip with liquid helium. Likewise, the card on which the chip sits is glass fibers in an organic resin with plates and traces of copper. These materials all expand at different rates. You also have a lead alloy connecting the pins of the chip to the copper traces on the board. Size changes due to temperature will put stress on these solder joints - and size changes in the plastic casing that holds the pins and integrated circuit chip will put a lot of shear stress on these weakened solder connections.


    So, this is not something that can safely be ignored forever.


    Likewise, electromigration will seriously reduce the lifetime of any chip being run significantly faster than its standard clock speed at room temperature. Electromigration is the tendency of metal atoms in wire traces on a chip to flow along with the direction of current. The higher the level of current, the greater this effect. If a chip is operated with too-high current levels for too long, enough metal atoms flow that the trace becomes brittle enough to snap under mechanical and thermal stresses, or develops a gap, or gets thin enough that resistive heating melts the trace or increases its resistance enough that it can't transmit signals properly. Electromigration effects were a common cause of failure in older chips. To compensate for this, chip designs nowadays specify maximum currents for given sizes of traces and are careful not to exceed them. However, overclocking _does_ exceed them. In order to clock a chip more quickly, you have to charge and discharge the parasitic capacitances within it more quickly - which is done by increasing the amount of current flowing through transistors in their "on" states. Conventionally, this is done by cranking up the core voltage. Cooling does this by lowering the threshold voltage and fiddling with a few other transistor behavior parameters. In both cases, for a chip clocked n times more quickly, you have n times the amount of current flowing through the same traces. Clock a chip at twice its normal speed, and you have twice the current through the traces - and a chip that will burn out far sooner due to electromigration. Copper is more resistant to electromigration than aluminum, but the metal traces in copper chips are correspondingly thinner than the metal traces in aluminum chips. This is why copper was adopted; the aluminum traces had to be made wide enough that bulk and parasitic capacitances were becoming real problems. Modern chips - copper or aluminum based - are designed to run just below the threshold for electromigration damage. Overclocking them to the degree being done with these cooled setups _will_ push them over the threshold.


    OTOH, if you don't care if the chip burns out in a year or two, go for it. Just be aware of the limits and side effects.

  • would it be cheaper to just buy a faster processor and run it at room temperature?

    Bah! Now where's the fun in that?
  • Once you take into account the cost of buying the refrigeration equipment and the increase in your electric bill from running it, would it be cheaper to just buy a faster processor and run it at room temperature?

    Yeah, I know, for some people it wouldn't be as much fun, but....

  • you can have hi-temp superconductors on-chip.
    That will be quite interesting.
  • open up a chip package, protect the bonding wires, and coat the chip with a protective layer, then spray chilled liquid refrigerant onto the chip. Idea would be evap. cooling. Got back a very nice message that said they're sticking to vapor-phase cooling for now, iirc. Popping open a CPU takes a lot of courage (and knowledge of how to keep it alive); I'd say you need to know more than you do to work on the head & disk assy. in a HD.
  • The glycol mixture isn't at -50C, the dual peltiers are responsible for the temperature dropping that low. The Glycol mixture didn't get below -25C.

    We really should read more carefully before throwing out comments.
  • with a bare case inside a fridge, I think you would probably have short-circuits due to condensing moisture?
  • Kryotech sells these, they currently sell K63-500 systems and Tom of Tom's Hardware used one of their kits to make a Celery-618
  • Unfortunately, it comes with a built in heater

    Make that: "Fortunately, it comes with a built in waffle iron"
  • Well, in semi conductors, electrons must have a higer energy than the band gap in order to conduct. If you cool a semi-conductor too far, you wil remove too much of its heat (energy) so te elecrons will not be able to "jump" the band gap and therefore there will be no conduction (infinate resistance)

    Keep in mind that this is a first order, mostly-classical (ie, not alot of quantum mechanics) approximation. One could take in the fact that electrons are fermions, and as such obey Fermi-Dirac statistics. But that doesn't come into effect until you are at MUCH cooler temperatures (Liquid helium, 4K and below)

    -- A wealthy eccentric who marches to the beat of a different drum. But you may call me "Noodle Noggin."

  • Tom's Hardware [tomshardware.com] also has a great OC blurb up right now.

    Sweet Jesus is that fast.
  • Why don't ice crystals form on this and break it?
  • Temp cycling or chip-board differential is what'll kill your CPU
    As long as you keep the board and CPU both at the same temperature and dont turn the coolers off more than once a day, you'll be OK.
    Otherwise the thermal expansion difference between the chip and the board will build up stress in the solderballs that attach the chip to the board and eventually crack them. We did that as part of chip Package Qualification. 1000 cycles and no failures were necessary to pass Qual.
    Your other problem is that commercial chips are not characterized to run below 0C, so you may work ok, maybe not, the usual overclocking problems apply. Not all parts of the chip may work correctly below 0C.
    The other thing is, the package may be at -50C, but the die really is at the ThetaJC*PowerDissipation. A good package is about 1/2 Deg/Watt, a 600MHZ PIII is probably burning about 40 watts, so If the case is at -50C, the die is at -30C.
    -55C is what Military parts are tested at. They are also constructed differently than commercial grade parts to deal with the Mil Temps -55/125C.
  • Also, it takes quite a while for thermal damage to involve anything deeper than the skin. Even people trapped in burning cars or buildings essentially never have burn damage to underlying fat or muscle (unless they die and remain in a fire for an hour or so).

    Yes, but even without damage to fat and muscle, you are still dealing with third degree burns which can easily be fatal if they are large enough or if you are old enough. If you don't die from septic complications, you may wish that you did after you have a look in the mirror.

  • Yup, the company is Kryotech (http://www.kryotech.com)

    Also, see
    http://www.kryotech.com/articles/chess_release.a sp

    for the details on how they cooled a 333MHz K6-2 to -40, clocked it to 450MHz and then ran a chess program called "Rebel" to beat World#2 Vishwanathan Anand 5-3.

    Currently they provide a PC with a 600MHz K6-3 CPU. So, I wonder why they don't try this on
    an Alpha :). Or maybe Alphas can't be overclocked so easily as Intel's chips?

    Yumpee
  • Wouldn't it be cool (no pun intended) if there were an all star wrestler of the name "Superconductor Cold"?
  • I've been interested in this sort of thing for a long while and have been overclocking since the old 8088 days when it took a soldering iron and crystals from the local 'Shack.

    Anyway, cooling with refrigerant has never really appealed to me much. There may be some danger in working with the Freon, I'm not terribly familiar with the technology involved, and the power drain could wind up being significant. Some of you have posted about simply placing a computer in a small refrigerator - this has already been done and it was found that the compressor in the 'frig couldn't keep up with the heavy heat load of an overclocked CPU - the compressor ran full time. The OCP article mentions this problem too, frankly I found the article very well written covering many bases most people forget.

    Anyway, my focus has been to build a water cooled Peltier assembly. I currently use Peltiers to cool a PPGA 300A enough to go 504mhz (stable) but the heatsink become significantly warmer due to the Pelt's heat. Obviously such a setup isn't ever likely to go below ambient either.

    Some have mentioned condensation and water as being really big issues. So long as the water is sealed out of your sink this isn't an issue. Condensation can be avoided by decent insulation - remember that condensation only forms when components cooler than the dew point meet humid air. Avoid this and you're fine.

    One of the last hurdles to consider (IMO) FSB speeds. Currently there just aren't enough selections and Intel's damned multiplier locking is making life a bitch. The Turbo.PLL the Japanese are working on may fix this as it'll allow you to vary the FSB in increments while keeping things liek the AGP and PCI cards at a normal speed.

    Way below are some URLs to check out. Note that some are in Kanji as the Japanese have really had a good time with this. Note too that Melcor sells components to water cool Peltiers for industrial applications and apparently not retail, someone needs to resell these parts! Lastly, the Socket 7 CPUs and the PPGA Celerons share a common size, the PPGA chips also appear to run cooler than their slot one brothers. My fastest systems all run the PPGA Celerons including one dual SMP system that's not actively cooled but still gets 2X464mhz. Note that I've not yet managed to get a successful water system running but am working on it. Car heater cores work well for heat exchanges, RedLine Water Wetter helps improve heat transfer, and small fountain pumps move massive amounts of water - these are designed to be constant duty too. All Electronics sells Pelts cheap BTW.

    On with the URLs! Here are just a few of what I've got and I'd welcome correspondance on this subject if my HotMail 'box can handle it!
    ------------
    http://www.melcor.com/ - Industrial hardware cooling supplier
    http://www.agaweb.com/coolcpu/ English water cooling site w/plans
    http://e-sdi.com/west/intro.htm English water cooling project, self contained
    http://www.mune.com/mcp2.htm Japanese site, Kanji w/Multiple projects shown.
    http://www.kumagaya.or.jp/~touma/index.html Japanese hardware site - Kanji
    http://www.jah.ne.jp/~ken1/kenO.htm Japanese project - Kanji

    I'd post more but after 5 Netscape crashes I've got to run. Explore the Japanese sites and check out the Turbo.PLL if you happen across it - that site is slowly being translated. If this is of real interest I'll try to post more URLs when I've more time!

    Enjoy!

    P.S. no time to preview, hope it comes across okay!
  • Ice will only form in the presence of water (You are thinkin' "Duh!")

    They seem to have taken care of the condensation problem by insulating/isolating the CPU.

    I think what they are doing is awesome. I might get the balls and see what I can do with my old P200.

    RB
  • Perhaps non-cost-prohibitive PCs with gig chips will now be available sooner than predicted?

    Frankly, I'm having nice reminders of that part of "Zen and the Art of Motorcycle Maintainance" where he talks about useing part of a beer can as a shim.
    --
  • well, you could use the eat pump idea
    keep the cpu really cold (to refrigerate the beer)
    and pump the heat somewhere else (to fry eggs, heat the house, start fusion reactions)

    you know, keep the hot side hot, and the cold side cold
    ;)
  • At the '98 CEBIT I (indeed) saw a cyrix processor being cooled to about -35 C. The basic principle was different though. They compressed air, removed the water etc and let it decompress via some sort of expansion path on top of the processor. The system was quite small: about the size of a large computer.

  • CAREFUL THERE'S a CATCH

    I tried this, using very small copper tubing. It is VERY IMPORTANT that you find out what the DEW POINT is and not cool below it! You'll condense water on your motherboard, as I did. If you live in a humid climate or a dry climate with a swamp cooler, you must be very careful!

    Put a sensor on the chip and regulate the temperature, don't just go crazy!

    -rMortyH
    ________________________________________________
    I have no use for hardware with a purpose.
  • When I got the PIII's, they were restricted to 500Mhz. They Cost $780.00ea. No overclocking. Then for 155.00ea I bought 2 SL2WY wk37 PII 333Mhz and with the cooling system I am able to run stable at 620Mhz. I would have saved over $1200.00 if I had bought the Pii's in the first place.

    Supercoolin
    The guy who built the system
    Supercoolin@hotmail.com
  • I have move up to Anhydrous Ammonia (R-717) in order to achieve sub -100C. Standard CMOS devices today can operate in -120C to -150C without problems but can be clock at twice the speed that is safe at 50C. Improvements in the "doping" process at a relatively cheap cost will allow further cooling to sub -150C and at -202C you are restricted by the quality of the PLC and not the processor. 1.6GHZ would be the theshold of the crystal today.

    Supercoolin
    The guy who built the system
    Supercoolin@hotmail.com
  • You can see by the pictures that everything is insulated and sealed. You only have condensation problems if you allow the cooled components to come in contact with ambient are. Thats why you insulate and seal. The Slot1 is actually ideal because by adding a High-speed decoupler between the slot1 and the SECC2 you not only get line noise isolation but a thermal break from the motherboard to prevent transient heat from getting to the supercooled processor. At -60C you can safely increase the speed of any CMOS device by 70%.

    Supercoolin
    The Guy yhat built the system
    Supercoolin@hotmail.com
  • This is the same thing you have in a small 2.5cuft freezer. R-134A freon. 9oz. at 144psi high side -11psi low side. They don't explode. they get a leak and slowly loose pressure. What you have to fear is our enviromently friendly R-134a. Health risks from R-12 CFC NONE
    Health risks from R-134a Short term DEATH
    Long Term-Tumors on Testicals - Loose balls

    The greatest health risk of this system is direct contact with the thermal plates, sub -60C temp will burn you more serverely than boiling water.

    Supercoolin
    The Guy Who Built the system
    Supercoolin@hotmail.com
  • I suggest you do your research inot the effects of electro migration mitigation effects of supercooling CMOS devices. The thermal breakage occur when and only when you either cool each component at a different rate, cool it to quickly, or allow it to heat back up to quickly. Though your points have validity in the world of ambient. The physics of CMOS devices begin to change at -40C and below. Do your homework.
  • Load 3D Studio Max and render 12000 frames @ 1024x768x32 and then tell me a great your Celeron 618 is. I'll expect your reponse in about a week if you have enough hard drives to hold the data.
  • R-11 and R-12 are banned freons, you cannot purchase them "over the counter", R-11 requires that you have a halogen detector in the same room as the compressor - extremely hazardous. R-12 has zero heath risks associated with it, but was a CFC. Remember when then Senator Al Gore stood before the Senate Committee and feed than a line of crap so long that it make his boss Clinton a siant. R-12 and similar CFC's were banned. My point was that the "enviromentally freindly" replacement being shoved done our throats is very damgerous and should be handled with that in mind. It is not the system or it's design, its the freon choice your government has restricted you to. Hell im changing to Anhydrous Ammonia (R-717) (plant fertilizer) pull MSDS sheets on that one.
  • Wasn't there some news about a company that specialized in this sorta thing?
    They took a cyrix apart if I remember right, by cooling it to -40C. And used it against the world's second highest Chess GM.
    A deep blue alright...

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