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Notebook Cooling Strategies
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.
But it keeps an army of fans to keep my desktop cool enough to runs stabely, and it sounds like an aircraft carrier.
"The United States has no right, no desire, and no intention to impose our form of government on anyone else." - Bush 05
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.
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It's hard to believe that's how Micronians are made. Why don't we see it right now by having you both kiss one another?
I have a sony Vaio, and that thing sounds like a friggin jet engine when it's running. The fans are unbelievably loud. You can even hear them when on a plane. I highly doubt I will buy another Sony laptop.
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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.
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Ban laptops in Antarctica. http://www.boston.com/news/daily/09/iceberg.htm
There's hell to pay.
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.
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.
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...
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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
Soccer Goal Plans
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..
..........FULL STOP.
There's this article I found... some people have developed ways to cool silicon using nothing but silicon! Here's the article. 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.
I'm the Devil the Windows users warned you about.
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.
*Condense fact from the vapor of nuance*
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.
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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?
**Life is too short to be serious**
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
that the only truly efficient cooling system is liquid nitrogen in a styrofoam cup!
--Chag
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.
"Prefiero morir de pie que vivir siempre arrodillado!"
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...
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). Maybe in another couple years when someone sues because of first degree leg burns received from their "laptop" things will change...
"The question of whether a computer can think is no more interesting than that of whether a submarine can swim" -EWD
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
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.
- - - - - - - -
Don't worry, being eaten by a crocodile is just like going to sleep in a giant blender.
Yep -- you can read about it here.
(shamelessly plugging my own site...so sue me)
--kurt
Gentoo Linux http://gentoo.org/
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
Gentoo Linux http://gentoo.org/
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
Power corrupts. PowerPoint corrupts absolutely.
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. *
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
More effective cooling - install a reservoir in the laptop, and fill it with freezer spray (freely available). This will cool the CPU/heatsink to -50 Celsius, just target the spray at the CPU.
A caveman dreams of being us, the incalculable power and riches. We dream of being Q, then what?
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.
Why bother.
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.
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
Bill Gates buys Itanium, then can't sit down for a week. He sells Itanium then optimises and removes bloat from Windows.
A caveman dreams of being us, the incalculable power and riches. We dream of being Q, then what?
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.