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Hardware

Notebook Cooling Strategies 163

Posted by michael from the lap-burns dept.
An Anonymous Coward writes "As components shrink, heat control becomes critical. Hitachi will sell water-pump cooling for notebooks while Sony has fancy, twin-fan ductwork in its new Vaio laptops. Meanwhile, a ceramics company that's testing a coating that's highly efficient in radiating heat away from processors and race car engines." We mentioned the water-cooled notebooks earlier.
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Notebook Cooling Strategies More

Notebook Cooling Strategies

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  • But it keeps an army of fans to keep my desktop cool enough to runs stabely, and it sounds like an aircraft carrier.
    • There is no reason a system has to be that loud. Generally, removing the case venting will reduce a lot of the turbulence (and thus noise) in your system. Additionally, you can replace your fans with cooler ones like Papst or Panaflos.

      The noisiest (or at least most annoying) components in a system tend to be the small fans, such as CPU fans and video card fans. You can replace those with passive heatsinks and then run larger (quieter) 80mm case fans to maintain enough airflow to keep things quiet.

      For more information on keeping your system quiet, see the web site in my sig.

      --kurt
    • Get a Noise Control Siverado CPU heatsink and fan. Get a Zalman chipset heatsink. Get a Papst chipset fan if you want, I did. Get some Silencer 80 or 92mm case fans from PCPowerandCooling. Use the Silencer in the case and also in the power supply. Crack it open, cut two wires, unscrew the current fan and solder in a new one. Adda case fans are good too. I have all of the above. I spent over $100 but my computer tops out at 35db from the CPU fan. Everything else is 20-24db. Since the quiet fans don't move as much air I have to have more fans. Anyone who bitches about how noisy their computer is needs to replace the crap that came with it.
  • to see how this technology proceeds. I can see some interesting applications if efficient heat dissipation techniques like these become more commercially prevalent, although it would also be nice to see the progress be made on the proc side instead...

  • IMO I think that ceramic-based cooling systems are going to be the way that things like this are cooled in the future. The cooling capacity of ceramics is much more economical than mechanical systems. Examine the space shuttle's cooling capacity vs. weight, complexity, and cost of other traditional systems.

    Imagine your car being cooled by a ceramic plate that never rusts, never needs refilling, and won't kill your pets. Sure it might break, but the cost to replace a ceramic cooling system will be much less than the cost to build a radiator.

    • Isnt that backwards? I tohught the tiles on the space shuttle were good at not absorbing heat and keeping it from transfering to the interior parts of the shuttle. But for a processor cooler you want to transfer heat away from the cpu and out into the air. Thats why they use copper and such, copper soaks up and distibutes heat well. So putting ceramics around your cpu would only heep more heat in, right?
    • Yeah but will it be cheaper if it breaks every couple of days or every time you hit a decent sized pot hole?

      I'm no ceramics expert so I would love to hear about what is going on regards to finding good ceramics applications and how they are getting around how brittle the stuff is. (I'm not sure if that's the right word but it breaks easily)

      The space shuttle uses those ceramic tiles but they have to constantly be replaced.

      And last but not least - current automobile engines are cooled by fluid and the fluid is cooled by the radiator. I have doubts as to whether ceramics are efficient enough that the cooling could be done w/out a fluid that moves around in the block, etc.

      Mostly I'm just curious and these are some of the thoughts your post evoked in my mind.

      .

      • Ceramics can be very strong (not really sure how high strength ceramics conduct heat though), the problem is that their molecular structure doesn't lend it's self to stopping fractures once they begin. This problem has been solved by people (esp. Porsche) developing ceramic brake rotors, by having carbon fibres embedded in the material.

    • ...and won't kill your pets

      You say that like having an inexpensive treat for the neighbors dog (who never shuts up) is a bad thing.
      --
      Sanity is the trademark of a weak mind.
      -- Mark Harrold
  • My Sony Vaio is a couple years old, no fans, lots of heat, enough to burn my legs if I'm wearing shorts. I talked with someone at a CES who was demoing some lap props to hold up laptops, suggesting they consider a model with an aluminum plate or such to wick away heat.

    Lately I've found if I want to prop it on the corner of my bed to place a few silver dollars under it, which works pretty well as they elevate it, give some ventilation and also wick away heat rather effectively, but perhaps not for everyone. :) Old cruddy silver dollars can be found for ~$7 each at coin shows and about a dozen works well.

    • Re:My Sony Vaio (Score:1, Offtopic)

      by atrowe ( 209484 )
      Wait, you paid $7 for a silver dollar coin? If you want even more efficient cooling, I'll sell you 100 pennies for only $9.99.
      • 12 1.5" disks of 90% AG, 10% Cu, work very effectively, considering the insulative nature of a mattress. They stack out of the way easier than contending with a pile of change, which I tried first. BTW, cents are now Zn, you have to get them from before 1982 (excepting 1943) to get 90-95% Cu. (1943 were steel)
    • I personally have a Dell Inspiron laptop, and like any desktop replacement notebook, it gets extremely hot after even short periods of sustained use. One thing I've found that works wonders for not only helping keep it cool but also with making the computer easier to work with for extended periods of time is a simple little item called the Podium CoolPad [devdepot.com]. While it seams amazingly simple at first glance, it's amazing how effective it can be. I can't recommend it highly enough.

      I'm not in any way affiliated with the retailed I linked to, they're just one of the few around who actually offer the product.

  • My notebook (Score:3, Funny)

    by stoolpigeon ( 454276 ) <bittercode@gmail> on Friday May 10, 2002 @04:27PM (#3499433) Homepage Journal
    tends to cook my legs very well now. If it were able to conduct heat any more efficiently I believe it would become too painful to use. On the other hand that kind of thing could lead to a lawsuit that would get me out of the daily grind and into the life of luxury I deserve.

    Ceramics are cool - I love ceramic knives but they are so easy to break.

    Water cooled laptops would make for 'funny' commercials with guys crawling over sand dunes gasping "water!, water!" and then pouring it into their computers. I could be a marketing genius.

    .
    • tends to cook my legs very well now. If it were able to conduct heat any more efficiently I believe it would become too painful to use. On the other hand that kind of thing could lead to a lawsuit that would get me out of the daily grind and into the life of luxury I deserve.

      Get a lap desk. Keeps your legs cool, plus your computer is more stable and has better air flow.
    • Did you see that dual screen notebook the other day? The coolest thing about it wasn't the two screens, but the TRIPOD SCREW MOUNT underneath! A solution to the sweaty legs problem! It's like a desk you can carry in your laptop bag. Some of those tripods can get pretty small.
    • This is somewhat offtopic, but ceramics are not as breakable as people think (teacup hitting a concrete floor).

      There are hammers made out of ceramics and internal combustion engines. These are pretty much the most extreme applications - both involve high resistance to impact and high pressures.

      The hammers actually outlast steel hammers, and ceramic engines are almost impossible to wear out. I'm not sure if it's the price or the engineer knowledge that's keeping them from being widely used. After all, the properties of steel and aluminum are well known to all engineers - those of ceramics aren't.
  • Comment removed based on user account deletion

    • Re:sony (Score:1, Funny)

      by Anonymous Coward
      i always wondered what that noise was when i saw planes flying overhead. YOUR DAMNED VAIO!! :-P
    • I have a Dell Inspiron 8100 and it's quiet as a mouse, until it starts to get hot. When the fans go into high gear, I swear it tries to liftoff. Also, the vibrations from the fans hurt my wrists when I'm typing. Thankfully though, the fan doesn't kick on very often.
  • Now how long will it take to get Coppertone 1500 (with Cerac alpha-1500 heat dissipation)?
  • I purchased a HP Xf145 notebook from Sam's Club about 1 month ago, for the price it was a great machine, 1ghz mobile amd, 20 gig hd, 512Megs of ram for $1200. Only problem is that it locked up randomly, and frequently. HP refused to acknowledge that there was a problem and I ended up returning it to Sam's Club for a full return. (15 day full return). I ended up purchasing a Toshiba Sattelite 5005-S507 that I can't be happier with. It cost me a bit more (~$1600, I bought it refurbished) and it features the Geforce4 chipset, 1.1 ghz true p3, 512 megs ram, 40 gig hd, firewire, 8x/4x/cdrw/dvd combo drive and many other features. Even though it has a full desktop processor in it I have yet to have a lockup on it and it's as stable as anything I've ever ran.

  • Still Need to Solve Hard Drive Noise (Score:3, Informative)

    by geoffsmith ( 161376 ) on Friday May 10, 2002 @04:31PM (#3499457) Homepage
    I find no matter how quiet they make these cooling systems in both laptops and desktops, water or air-cooled, its the hard drive noise that's drives me nuts. I use SilentPC stuff, including their hard drive cover, but I still find that high pitched whir of the HD is the loudest and most irritating thing coming out of my box.

    Now sure I can get my hard drive to spin down when not in use, but even when I'm not sitting at the computer there are many a cron job that need to get done, and when they write to disk the hard drive spins up again. Apparently IBM's drives are supposed to be quiet, but I got one and they are anything but.

    Websurfing done right! StumbleUpon [stumbleupon.com]
    • Apparently IBM's drives are supposed to be quiet, but I got one and they are anything but.

      IBM Drives can be quiet, but very often you have to use their drive tuning software in order to get them to be quiet. Search around the IBM website for this utility. Unfortunately, you pay for the quiet drives with some amount of performance. Also, I am not sure if this tuning program applies to laptop drives.
    • I have a powerbook g4, and it's pretty quiet. The drive isn't very noisy, and the fan doesn't always come on.

      When I'm using lots of cpu, the bottom heats up nicely. Then the fan kicks on, the first level of fan isn't very noisy. If I'm listening to music or if there is any ambient noise I can't hear it very well. The second level though sounds like a little hairdrier. Luckly this only really happens when you are using 100% cpu and the computer is on a bed or something.

      I have a podium coolpad and it does wonders. It helps keep the fan off during casual use.

      But I had this crappy dell notebook once, and it always heated up like a sonfabitch and the fan was _noisy_.

      Apple notebooks rule ;-)
      • I don't have an Apple notebook, buy a few of my friends do and I agree they are by FAR the quietest computers I have ever not-heard. =)
        That shouldn't be a surprise though, all of Apple's latest computers are quiet, almost makes me want one.
    • I actually kinda like the little clicking of harddisks in the background. it reminds me that all is well in the world. I want the rest of it to be quiet, but I find the light clicks kinda relaxing.

      dave
    • The quietest drive I've had so far is the one in my current machine, a Seagate Barracuda IV. It's not silent, but it's a LOT quieter than my previous IBM drives. Can hardly hear it spin up, and it rumbles quietly when accessing rather than the irritating series of clicks that the IBMs produce.
    • What you want is a Seagate Barracuda ATA-IV. They have fluid bearings and run so quiet it's startling. I upgraded my TiVo to a 60Gb Seagate and a Vantec Stealth cooling fan, and now I literally cannot hear it (except for occasional seek noise during heavy activity) when I'm sitting on the couch, 12 ft. away. My desktop machine has the 40Gb version and it's just as quiet.

      Once you solve the hard drive problem, your next issue is the cooling fans. At this point I have a near-silent CPU cooler (the Vantec Stealth again), and a near-silent Panasonic Panaflo case fan that usually isn't even running. The loudest component is my power supply fan, which I might try to replace soon.

      Of course, when you have to go unplug the refrigerator to be able to hear which component is making noise, it's arguable that your PC is already as quiet as it needs to be...

      -Graham
      • Don't be afraid of your power supply unless you are an absolute klutz with a soldering iron or have a magnetic-like attraction to powerful capacitors. The fan in my power supply is 80mm and I think that is standard. Buy whatever you like. The Silencer fans from pcpowerandcooling.com work great for me. Cut two wires, unscrew the two screws holding the fan in place. Solder, I had a third hand help since the wires were mid-air over my case. Screw in the new fan and screw the supply back together and to the case. The capacitors are far from the fan and wires in my supply.
    • Here's a great solution [silentpcreview.com]. Basically, take two sheets of 3/8" aluminum and make a hard drive sandwich. Pack some stuffing around the side and you have an ultra-low noise HD. The aluminum also acts as a heat sink, so you get the added benefit of better heat dissapation.

      (full disclosure: I run this site with a colleague of mine)

      --kurt
  • No probs. Just put it in the freezer and it will be icy cold in the morning when you take it to work.
    • ouch really really really bad idea. even a laptop hard drive can (internally) climb WELL above ambient temps. mix in a cooled substrated with moist air and what do you get? CONDENSATION. and a single bead of dew is enough to royally ruin your HD's day. The little membrane for the HD to breath is not watertight and does not filter out moisture in the form of humidity. Now maybe this changed in the year since I first read about this. But I really doubt it.
  • I have to change the radiator fluid in my computer. Perhaps the colder regions will require anti-freeze (no longer for just software, for hardware as well)
  • Ban laptops in Antarctica. http://www.boston.com/news/daily/09/iceberg.htm

    There's hell to pay.

  • There's another solution... (Score:4, Interesting)

    by Qwerpafw ( 315600 ) on Friday May 10, 2002 @04:36PM (#3499482) Homepage
    One could always inspire computer makers to simply develop more heat-efficient chips...

    This has the added benefit of increasing battery life, as in most cases heat emission is proportional to power draw (all that energy has to go somewhere, and it usually comes out as heat).

    Motorola has done a pretty good job, probably b/c their main market is for embedded systems. This has the result that Apple laptops are remarkably power efficient and give off little heat. My iBook's fan has *never* turned on since I bought it about a year ago. It has gotten warm, but the fan hasn't ever needed to turn on. tiBooks have G4 chips, which are less "cool" while running, so PowerBook G4 fans turn on more often. And I imagine the transmeta Crusoe is similiar, though i've never used a Crusoe laptop

    But still, one would imagine it would be cheaper to develop more energy-efficient chips, rather than simply finding ways to vent that energy. Of course, If venting must be done, I am all for fractal-geometry heatsinks at the nano-level (maximizes surface area in which heat venting can occur, for a lot less price than water cooling, not to mention being very nice and quiet), but thats a topic for another post :)

    Anyways, my point is that it might be better to develop a solution at the chip level, rather than have to compensate for power-guzzling chips by having obnoxiously loud and edxpensive cooling solutions.
    • My iBook's fan has *never* turned on since I bought it about a year ago.

      Is that a toilet seat model? The 2001/2001 "IceBook"'s don't have any fans. The only parts that move are the HD and DVD, if/when you spin them up.

      Mine is also wonderfully quiet with good battery life. The only time ever gets warm enough to bother me is when it's on AC power AND is left sitting on a soft surface like a bed, or my leg. Actually, I've since tweaked the power management settings so that the HD is allowed to spin down while on AC power, which fixes that too.

      - RustyTaco
    • I agree with most of your post, with all the technology we have, it ought to be possible to develop an ultra-low power, ultra-low heat chip that does all your word processing and spreadsheeting and emacs/vi coding without breaking the bank. In fact, if I understand it correctly, the Crusoe IS such a chip.

      Unfortunately, you're wrong about it being cheaper. A water pump is orders of magnitudes cheaper to engineer than a completely new chip. Furthermore, the total abject failure of the Crusoe in the marketplace seems to suggest that few people will make the tradeoff of higher price and lower performance for less power and less heat (unless, of course, it comes in fruity colors [apple.com]). Maybe in another couple years when someone sues because of first degree leg burns received from their "laptop" things will change...

      • Re:One quibble (Score:2, Insightful)

        by Qwerpafw ( 315600 )
        can't resist....

        1stly. No mac comes in fruity colors. Ha.

        2ndly. In the short run its cheaper to use a water cooling, but long run its cheaper to make all mobile chips be more power efficient. This is b/c you do research once. (fab costs aren't higher for more power efficient chips) Whereas every laptop has to come with water cooling, so it costs more.
      • Really a update of the old IDT Winchip, but given the Cyrix brandname.

        Its cool enough to use passive cooling, ie a fanless heatsink.

        Or just under clocking works well too.

        The AMD Athlon 4 mobil processor is really just a T'bird Athlon of about 1500mhz or something that's been clocked & volted down to 1000mhz.

        I'd say virtually any chip that can be clocked up without increasing the voltage should be able to be clocked down giving the potential for a good volt drop & corresponding heat drop.
    • qwerpafw wrote:
      My iBook's fan has *never* turned on since I bought it about a year ago. It has gotten warm, but the fan hasn't ever needed to turn on. tiBooks have G4 chips, which are less "cool" while running, so PowerBook G4 fans turn on more often.
      I tested the Ti Powerbook G4 @ 667 and found that during compiles the fan would come on and stay on. It is very, very loud, almost to the point of being disruptive. The solution, of course, was the use the wireless to ssh to a remote compile server and do the CPU intensive operations there.

    • Unfortunately it doesn't work that way in the PC world. In PC laptops, the chip maker provides specs to the laptop manufacturer and says, "be able to cool x watts of heat in your next design."

      The laptop manufacturer has to listen since nobody really has enough of the market to make the chip manufacturer do otherwise.
    • Power consumption on chips will most likely continue to rise into the future. Process technology shinks (025um -> 0.18um, for example) have long been used to lower power, but transistors have now gotten so small that they are essentially conducting even while they are supposed to be turned off. In addition, everyone tries to cram more transistors onto a chip to improve performance which uses more power. Finally, pipelining improves performance by allowing higher frequencies, but faster clocks use more power. The end result is that chips will continue to get hotter into the future. Patrick Gelsinger from Intel gave a keynote at the ISSCC 2001 conference showing graphs in this rise in power and said that power will be one of the biggest challenges faces designers going forward.

      In mobile apps, the majority of consumers pay little attention to battery life beyond looking for a minimum theshold (an hour and a half). In addition, since there is no defined way to test for power that is enforced between manufacturers, there is no easy way to compare battery life using the manufacturer's specifications. Performance sells CPUs in the mobile space - not power savings. At least not yet.

      As long as performance continues to be the key selling point of CPU's, the power situation isn't likely to get better - and, at best, can only hope to stand constant. Performance and power savings are generally opposed in CPU designs similar to the way fuel economy and high-performance engines generally are opposites. Even if power becomes the key selling point, the future still doesn't look bright for power dissipation on chips. Current leakage in supposedly "off" transistors will continue to rise in future process technologies.

      * Not speaking for Intel Corp. *

  • laptop cooling = bad (Score:3, Interesting)

    by meatspray ( 59961 ) on Friday May 10, 2002 @04:37PM (#3499490) Homepage
    The fact that the portable device is generating that much heat means you're loosing a lot of your precious battery to resistance, not a very good use of your battery life.

    they should be mainly concerning themselves with lessening energy consumption and keeping the same performance if they really want to make something worthwhile. unless of course someone wants to come out with a dual processor notbook, batter life would then infact be a moot point.

  • what about macs? (Score:2, Insightful)

    by hexdcml ( 553714 )
    I used to have a Vaio, and like others, I have expereinced leg cooking heat when using it as a 'laptop' (that is if the battery ever lasts that long). Plus, the fan was noisy - there is an option in the Sony Power management software to switch the fan off, however, i think performance is comprimised.
    I've now got an iBook, and not only do my legs stay cool.. it is also extremely quite (no fans, just uses convection currents if I'm correct), the only sound being the harddrive below the left palm rest.
    Personally, I think Apple notebooks are the quietest. Less heat/noise = less energy is wasted thus, longer battery life... :-)
    • I'm pretty sure the iBook has a fan, it just never turns on. My 2 year old 400MHz G3's fan has come on exactly once, when I had it sitting on the bed, probably with the vent blocked. Sitting on a smooth table running RC5 decryption [distributed.net], my processor's internal sensor peaks at 147 degrees F and the fan doesn't turn on. The G3 is particularly power-efficient compared to Intel processors, the G4 less so.

  • My Dell C800 (Score:3, Insightful)

    by peterdaly ( 123554 ) <petedaly&ix,netcom,com> on Friday May 10, 2002 @04:41PM (#3499514)
    I have a Dell C800 (1ghz) laptop. When the fan comes on, people look over...when the second comes on, people dive for cover. (Well, maybe they are not really that loud) It would be nice if they could sync the RPM's a little better so it doesn't have the "whir" "whir" "whir" sound. That's the price I have to pay for a 1st gen gightz laptop.

    I've got some copper piping stuff going from my CPU to the fans, which supposedly has some super heat conductive stuff in it.

    -Pete
    • I have a C800 (866) and a C810 (1.13), the C810's have even louder fans then the 800s... I know exactly what you are talking about, if also does a decent job of roasting my lap.
  • I guess there are three available options for cooling here. 1 - Active (fans, coolant circulators, Peltiers anything else?)....2 Passive (fin type radiators, coolant circulators) ... and 3 -Mixed solutions (passive + active when using intensive CPU)...
    It stands to reason that since battery life is always a concern w/ laptops then passive cooling should always be used, and if not sufficient then some active cooling as well. In arid areas (Southwest USA) evaporative air conditioning works very well so an evaporative strategy might work - however you're screwed once you hit the east coast i.e. Washington DC.... My low tech solution is obvious...use a readly available heat sink that is non-toxic, cheap, easy to obtain....ICE WATER You can get it anywhere you go (airplanes/7-11s, etc) - just add a temp sensor to your laptop to indicate when you need to build up some coolant reserves.. It shouldn't take that much engineering to isolate any condensation problems..
  • I prefer using my laptop outside in the middle of winter in Wisconsin. Luckily I will be going to Michigan Tech next year so the same cooling method will still work.

  • Cool Silicon! (Score:4, Interesting)

    by Devil's BSD ( 562630 ) on Friday May 10, 2002 @04:47PM (#3499542) Homepage
    There's this article I found... some people have developed ways to cool silicon using nothing but silicon! Here's the article. [cerncourier.com] I remember also a little side article about refrigerating silicon (the silicon acts as a active heat dissipater) in Popular Science a few issues back but I'm too lazy to dig through my room or do a web search.
  • What I'm wondering is why no one has attempted to regenerate that heat back into usable energy. Sure, there will be significant losses, but if you end up with a net energy profit, it is probably worth it. Other potential drawbacks include increased weight, cost and complexity. However these are all things that engineers, over time, could overcome.
    • you might be able to use a water cooled laptop as a steam engine: kind of like a nuclear powerplant, the steam generated by the heat would turn a turbine, then would condense and recycle.

      The problem is that it would have to get pretty hot for that to work. Hot enough to fry your legs. And the watercooling rig would have to be pretty bulky. To shield you from the heat, you would have to put in a bunch of heavy shielding. So you'd end up with something the size of a deksotp.

      Another option for heat would be to utilize a heat gradient for energy via some kind of advanced circuit-kind of like a solar panel. But I have no clue how that would work.
        • Another option for heat would be to utilize a heat gradient for energy via some kind of advanced circuit-kind of like a solar panel. But I have no clue how that would work.

        The thermocouple effect. I understand that some Satellites were designed to use thermocouples to generate electricity based on the large temperature gradient from their side facing the Sun vs. the side away from the Sun.

        I don't know if it'd be practical, typically thermocouples only generate very small currents, but it is an easy and well understood way of coverting a temperature gradient into a current. If more efficient thermocouple metals were expensive, then this could be something that could be recycled when an old laptop was trashed.

      • How about a heatsink with an integrated stirling cycle engine driving a fan blowing across the cool side? Or a liquid cooling system circulated by a stirling engine? Neither of these would contribute energy directly back to powering the laptop, but they would save the batteries from running an electric fan or pump.

    • by th4e second law of thermodynamics, trying to use this type of heat to produce work is not very useful at all. By Carnot Cycle, Effiency = 1 - (temp of cold sink (ambient temp))/Temp of Hot source (laptop)) say the chip got hot enough to boil water on, 100 degrees C which is 373 degrees K, ambient temp is about 25 degrees C which is 298 degrees K so the effiencey of this would be about 20 percent effient. no chip gets that hot, so realisitly its more like 50-60 degrees C while drastically lowers the effiency, and still thats only on waste heat. you would still have to gather all of that enegrry somewhere and create a large temperature graident to make use of that eneggy, no trying to recycle the waste heat is not cost effective it would be more effiecnt to make more enegery effiecnt chips. the energy recovered from the heat might be enough to maybe power an led :)

    • Net energy profit? (Score:5, Funny)

      by IntelliTubbie ( 29947 ) on Friday May 10, 2002 @06:34PM (#3500015)
      What I'm wondering is why no one has attempted to regenerate that heat back into usable energy. Sure, there will be significant losses, but if you end up with a net energy profit, it is probably worth it.

      Net energy profit? Young lady, in this house we obey the laws of THERMODYNAMICS!!!

      Cheers,
      IT
    • Maybe you could add some reversed peltiers to get some current out of the temperature difference, and use em to power your fans. Then, the hotter it gets, the faster your fans go :)
  • I seem to recall a recent batch of a very lightweight carbon based foam that was VERY effective at conducting heat. Perhaps such a substance could be used as a solid "heat pipe" to a larger area of same such substance on the back of the notebook screen (to avoid that "hotlap" syndrom all of us that use P4's know too well). I know there are probably major challenges to such a system, but I have it working (in principle at least) in my heat storage in my solar greenhouse. Heat conduction does not have to be liquid. I am sure there are a few esoteric solids out there with the correct mix of performance and price. I know liquid cooling is both efficient and cheap, but I have serious doubts about the longevity of such systems in practical use. Laptops and portables of all kinds take more abuse than Bill Gates at a Linux Convention. I shudder at the thought of my pride and joy springing a "leak" on a business trip and ruining my day AND my data. Just my 2 cents.

  • Innovative Uses (Score:2, Funny)

    by ghoul ( 157158 )
    Now that we have a portable water heater free with our laptops maybe we could put it to good use

    1) We use it as a coffee maker. Just add a USB (Ultra Strong Beans) port and let the laptop do its stuff

    2)Power generation. Use the heat to make steam . use the steam to turn the mini turbines which can replace the fans and use the power generated to recharge your laptop.

    3) Fight against terrorism. Add a nozzle for squirting super hot water. Any terrorist trying to take over a plane would face 20 streams of boiling hot water in his face.

    Any other suggestions?
  • I thought it said "Notebook Cooking Strategies" I often fry eggs on my titanium ibook, Apple's non-stick coating is the best!

  • Possible Avenues (Score:3, Insightful)

    by Effugas ( 2378 ) on Friday May 10, 2002 @05:00PM (#3499609) Homepage
    1) We're going to finally start seeing hard-drive free systems. RAM is actually cheap enough that one to two gigs, living off an independent power supply, should be price competitive with a ten gig hard drive. Though XP might need to be shaved down a bit to fit in such a small amount of space, the increased system speed and vastly decreased amount of moving parts should make a significant difference in both power consumption and heat generation(the two are arguably the same thing). On the flip side, repeatedly pulsing that much memory might actually drain more power than I'd guess, and battery life on the RAM might not extend past a few days. In this case, I could still see a microdrive + RAM combo, or even a system that flat out just ran off a 2gb microdrive.

    2) CPU heat will eventually be turned into a power source. Heh -- it's there, it's dependable, and if nothing else, it'll supplement primary power sources. I don't know how efficient electrical heat->power systems are -- I doubt Peltiers are going to work too well here, and we ain't sticking a turbine into a laptop (though Microfluidics just got much, much more interesting!). So this is the "five-to-ten years down the road" likelihood.

    3) I feel like sounding like an idiot for a second, so I'll put this out there just for someone else to discredit: What about mechanical compression? Imagine a spring on the side of a laptop that needed to be pushed in periodically, but would absorb heat by slowly expanding. It'd be annoying, but each time the spring was compressed, heat should be lost reasonably harmlessly to the user's musculature. I'm sure this doesn't work, but I'd be interested in knowing the history of why not.

    Yours Truly,

    Dan Kaminsky
    DoxPara Research
    http://www.doxpara.com
    • sure, it would absorb heat, but when you compress it, or just compressin a long spring.
      Basically your trying to convert heat energy into mechanical energy, adding energy to it isn't going to get you less energy.
      the only real anenue, in my ind, is to develop a better system. Like proper dual cpu system, running good a parrel OS. both at about 400MHz.
      Or here is an even briter idea, stop trying to turn notebooks into gaming machines. VERY few people need a 1gig laptop.
      • Remember how a fridge works -- a gas compressed loses heat. Total system heat increases, of course, which is why the ice cream coolers always had hot grades. But the heat is far away.

        Hmmm. Maybe a normal spring and some gas that responds acceptably to being compressed by human force? I dunno. This is *so* not my specialty :-)

        I have the suspicion that building machines with solid state hard drives would create a larger performance gain than the next three generations of Pentiums.

        I do fail to see how two CPU's would be more power efficient than one.

    • I've been lusting over Sandisk's FlashDrive [sandisk.com] for about two years now, ever since I bought a Siemens Linux terminal whos primary disk was a 16MB flash with an IDE interface. I still have that box (it only has a 200 mhz cpu, but it runs linux great) and am waiting for the day that the 1GB flash drive hits $300. I will then have a very useful, completely quiet, and almost free of heat PC. :-)
  • One of the major problems with laptops today is that they are very difficult to actually keep on your lap. Most have either air intakes or exhausts on the bottom, so keeping them on your lap can plug the intake and make the machine overheat. The situation is even worse when sitting the machine on something soft like a blanket -- it completely plugs the air holes. I like using my vaio to watch movies while lying on my bed, but I have to put a book under one edge of it to keep the bottom from being in direct contact with the blanket; if I don't, I can certainly feel it heat up very quickly.
  • When we hear about some hardware geek using water cooling to ratchett up his l33t box to 3 ghz we think he's crazy. But when Dell does it, it's news.
  • that the only truly efficient cooling system is liquid nitrogen in a styrofoam cup! [vr-zone.com]

  • Problems in the past (Score:2, Interesting)

    by Chagatai ( 524580 )
    I remember hearing from some people who worked on laptop design in the past for IBM about heat issues with laptops. Most of us take for granted that we have the ability to feel things with our legs. Well, when some models of laptops were released that didn't have good heat dissipation, parapalegics (sp?) were subsequently getting nasty burns on their laps as they couldn't feel the heat radiating out as much as normal folks. Consequently, laptop designs had to be changed quickly. So, laptop cooling is not just a matter of being 1337, but a potential health concern as well.

    • That reminds me of a problem we faced with(Analog) Cell Phones: The speaker area would heat up due to closeness to (transmit) Power Amplifiers and "burn" users ear lobes (thermally, a very sensitive organ - did you know that!) The product had to be modified (at great cost) due to consumer complaints.

  • Waterbooks (Score:3, Funny)

    by InsaneCreator ( 209742 ) on Friday May 10, 2002 @05:50PM (#3499815)
    Hitachi will sell water-pump cooling for notebooks

    Imagine you're using a notebook with water cooling in a public place and it somehow starts leaking. You suddenly have hot water running all over you and when you stand up you somehow have to explain how that big wet spot got on your pants in the first place...

  • Water cooling can't be the answer. . . (Score:3, Interesting)

    by stevarooski ( 121971 ) on Friday May 10, 2002 @06:20PM (#3499944) Homepage
    It just seems to me that water cooling is so. . .clunky. It takes a lot of energy to circulate water which has to come from somewhere. Water is HEAVY. And there's always the obvious problem of water around sensitive electronics, as anyone who's "water-cooled" a gameboy in the bathtub will tell you.

    One of my roomies has a water-cooled case, and the sucker is heavy, expensive, takes a lot of water, and sucks a ton of power. Keeps his athlon cool without a huge roaring fan, but if the thing ever tips over I would think he's out a lot of money. Not to mention the huge stain on the carpet.

    Water cooling can't be the answer for laptops; too inefficient, too heavy, and its a dated idea. I would think that chips that ran cooler would be a more long-term solution.

    Sides, if your laptop sprung a leak, I think a wet lap on a plane for 8 hours would be damn unpleasant.
    • The heavy part is right, but the only force the pump will be fighting againts will be any "friction" (it probably has some other word having to do with viscosity) and momentum. For instance, if you have a vertical loop filled with water and a pump to circulate the water through the tube. The weight of the water on either side of the pump will be equal, so the pump will not have to struggle, only ight momentum and "friction".
    • Actually, pure water isn't that electrically conductive. H2O happens to be one of those really stable and self-happy molecules, which is why it forms that nice skin you've noticed when you fill your water glass too much.

      Most of the reason why tap water wrecks electronics is because it contains a lot of free ions. Copper piping is erroded by the water, adding lots of little Cu+s to the water. Those are happy to take in an electron and potentially short-circuit your board. I use pure distilled water to clean electronics with no problem.

      Certain types of petroleum-based fluids are also very non-conductive, but very greedy about absorbing heat. Given the proper heat exchanger it's a very good solution to cooling.

      Plus, the right materials for the tubing must exist. When was the last time your brake fluid line burst? :)
  • Wouldn't anti-freeze work better than water? It works better in cars doesn't it?
  • The old Sun optical mouse pads were made of aluminium. I put one under the CPU unit of my ASUS B1 notebook. As long as it keeps in contact with the bottom of the laptop (rubber feet sometimes get in the way) it keeps it running cooler.

    Also, running Linux keeps the laptop temperature down compared to WinXP. Linux seems to be more efficient in that category as well! :)

  • Flourinert [sic] (Score:1, Interesting)

    by Anonymous Coward
    The leaking issue and conductivity of water has already been solved by 3M with their flourinert product. Conducts heat great, toss a running electrical device into a pool of it and it won't create a single short. My memory is a little fuzzy here, but it's not all that expensive (well much more expensive then water, but a lot less expensive then say printer ink cartridges). The only problem I see with water cooled laptops is the radiator/pump and keeping the system efficient without making it huge. It took me an enormous AT tower to make a self-contained water cooled desktop.
    • It took me an enormous AT tower to make a self-contained water cooled desktop.

      Perhaps the use of the fact laptops move n shift about constantly could be used somehow to help shift fluid around. It wouldn't help while the machine is on a desk, but as a little extra aid in-transit when quietness may be more necessary it may make the difference

      a grrl & her server [danamania.com]
  • Notebooks are doing some incredible things in the way of upping power/features/screen size/etc while shrinking drastically in size and weight - and ending up with some problems such as heat dissipation. In my mind the biggest advantage to a notebook apart from its' portability, is the weight issue - not size. Surely giving quite a bit more space inside the box isn't going to add all that much to weight, may bring a laptop an extra half inch higher while increasing air cooling possibilities incredibly.

    I can see that laptops have a high 'just plain sexy' component, which isn't likely to go away. A rep in a former workplace of mine insisted on one of the top Compaq notebooks, when his only need was for a PDA. Thin does sell for many people, but for me an iBook or TiBook would be just as nice at twice the depth.

    a grrl & her server [danamania.com]
  • More effective cooling - install a reservoir in the laptop, and fill it with freezer spray (freely available) [maplin.co.uk]. This will cool the CPU/heatsink to -50 Celsius, just target the spray at the CPU.

  • Blame the MHz war (Score:2, Interesting)

    by Wrexen ( 151642 )
    One problem with the new faster-than-God chips is that the clock signal has to switch every clock cycle (duh). Most waste heat comes from the switching from 1 to 0 or vice versa, so that shiny new 1.7 GHz P4 laptop is going to be making that clock signal heat 3 times faster than the 600 MHz machine you're using now. If CPU makers went for more aggressive parallelism (AMD for x86, IA-64 long term, etc) the clock wouldn't need to switch nearly as fast, saving us a lot of wasted energy. Of course, Joe Consumer is still only looking at the clock speed when buying a new laptop, so manufacturers are stuck to following the market and driving battery life into the ground
  • This post is targeted towards people who know the internals of a Dell Inspiron. It's kind of hard to describe, but bear with me. Basically, you have the CPU under a thick metal plate (of what type, I am not sure). Between that is the compound, and then a copper plate with a copper pipe squeezed into it. This pipe then goes about 2-3 inches to the right where it is joined to a sink and fan.

    I was having some severe overheating problems with my laptop (Dell Inspiroin 3800) for a while. I opened it up and discovered a less than ideal situation for moving the heat from the CPU's metal casing to the copper pipe that lead to the exhause (another sink with a fan on it).

    Betwen the Cu pipe and the CPU's casing was a piece of fabric with what appeared to be Ti-oxide (generic, crappy thermal compound) on it. I had just recently bought a tube of Arctic Silver II at a computer show, and decided to try it out. After removing the wad of junk, I put a nice glob of AS2 on the CPU casing. I wanted to make sure there wa sufficient quantity to ensure full contact between the uneven (kind of bent) and poorly designed copper piece. When putting the assembly back together, I put the frabic wad on top of the copper plate and between a bracket that held the thing together (to apply more pressure between the CPU's metal casing and the Cu).

    I managed to lower my CPU's temperature by about 5-15degF on average. I noticed when my fan was on, the air coming from the remotely located heatsink facility was a little warmer than before, indicating success.

    Conclusion: your laptop probably has a rather crappy cooling solution. Go to a computer show, get some decent thermal compound, and do a little hacking. Just make sure to test your setup a lot to make sure you actually made an improvement or at least a lateral move.

  • Phase-change heat pipes (Score:3, Insightful)

    by tbo ( 35008 ) on Saturday May 11, 2002 @12:28AM (#3501082) Journal
    are the way to go... I saw them advertised by an OEM a few years ago. Here's how they work:
    The heat pipe contains a liquid/gas that changes phase around the operational temperature of the device you wish to cool. At the hot end of the pipe, the liquid evaporates, sucking up the
    heat of vaporization [dictionary.com]. The vapor travels to cold end of the pipe, and condenses there, releasing heat. The inside of the pipe is specially-designed so as to use capilliary action to draw the liquid back to the hot end of the pipe. What all this does is give you a pipe that has an effective thermal conductivity many, many times better than a hunk of copper (which is already a damn good thermal conductor).
    Presumably, you use these pipes to move heat away from the CPU towards the outer chassis of the laptop.

    Looking inside my Apple PowerBook G4, I see things that look very much like pipes traveling away from the CPU to other areas of the laptop (areas which tend to get rather warm), and I assume these are the phase-change heat pipes I heard about a few years back. Whether Apple is the only company doing this, I don't know, but it is sure cool, pardon the pun. The fact that the G4 consumes less power is also a big help.

    I'm now going to go off on a tangent, mentioning various aspects of physics that are barely relevant, but pretty damn cool. First of all, a bunch of people have suggested using the heat as a power source. While you can use temperature gradients as a power source (think thermocouples), it's damn unlikely to be practical here (the power harnessed would be trivia).

    Second, I'd like to point out that heat dissipation is becoming an increasingly-important problem in CPU design. Although we're not there yet, there are theoretical limits on how efficient non-reversible computations can be, in a thermal sense. In other words, each time you manipulate a bit (to be really picky, each time you reset a bit), it must produce a certain amount of heat. This could be the hard limit that breaks Moore's Law for classical, non-reversible computers. The way around this is to use reversible gates (such as in quantum computing), which have no such minimum heat cost. For instance, the XOR gate can be replaced with the controlled-not (CNOT) gate, which is reversible. This would require a major reworking of how we build computers... But I digress... Suffice it to say, heat is a big problem, and it's only going to get worse.
  • ...typically, heat-related coatings on engine components are designed to keep heat *in*, so belts, hoses, and other non-metal parts don't get fried.

    I guess I could see an application to radiators -- parts that are specifically designed to radiate heat -- for some "heat-phobic" coating, but it seems highly unlikely. 1) Drag racers are concerned about a quarter mile that goes by in somewhere between 4 and 10 seconds; there's not enough time for heat to make it to these fancy coatings. 2) Road racers sustain speeds of 100mph+, and wind alone does a heck of a cooling job at those speeds.

    I can't say the racecar angle is bunk, but I can say it's the reverse of my limited experience in that field.

    -b

  • Simple solution (Score:3, Funny)

    by Beliskner ( 566513 ) on Saturday May 11, 2002 @05:18AM (#3501567) Homepage
    Simple solution - wearable computing. Attach the heatsink to the user's ass. That way when the user runs a CPU-intensive task it will *HURT*, encouraging him to buy a CPU that runs cooler like a Transmeta. Pentium owners and AMD overclockers will get permanent scars. This way we'll get more efficient software when these important Manager people start complaining.

    Bill Gates buys Itanium, then can't sit down for a week. He sells Itanium then optimises and removes bloat from Windows.

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