Well... servers don't share space with people in their living environments.... but this brings up an interesting point... do we have to have our computers in the immediate area where we use them?
I am not very computer savvy... I feel confident that watercooling is superior to air cooling because this is a subject that I have researched quite a bit. But... that doesn't mean their isn't a better solution even than watercooling.
Let's say that we store the bulk of the computer in a different location? What problems might this pose? Will there be performance losses doing this? Could this be done wirelessly? This would be ideal because wiring would be a problem.
Could you use pre-existing home wiring as the communication lines between the "home server" and the pieces you would need to work with(optical drives keyboard and monitor)?
I have to compliment somebody for resurecting this thread not starting a new one on liquid cooling.
Segway, many people, many people smarter than I, have explained that liquid cooling is ultimately air cooling. Believe them! I mean, where does the heat go after it goes from the processor to the liquid? Does it just disappear? Unless you had the computer connect to a lake or river it has to pass to the air.
And you would WANT a fan. The good thing about fans is that they give you control over the heat removal. Variable speed. Slowly, quietly running most of the time but the capacity to buzz if your wife puts a book right in front of the vent.
However, a fan with water cooling does not mean fewer, noisier fans than in air cooling. Why? Cause the radiator/heat sink is more efficient in liquid. A metal heatsink has heat passively conducting its way through. A radiator has the hot liquid pushed to all parts. So equal heat is spread over a larger area and you know the rest.
Notice the vanes(?) are slimmer and more numerous on a radiator vs. heatsink? In a heatsink why bother, you have to start with thick vanes to have enough material (copper or aluminum) to carry all that heat. And even if the sink branched out like an oak tree the heat travels too slowly to reach the final twigs to be worth the trouble. Also, the heat sink would resemble a tree in size too!
In the meantime, Apple has done a wonderful job with controlled fans in the G5. Ive heard a G5. But just barely.
I am not confident in watercooling, with time plastic tend to have fissures and joints are not so cohesive, escape of water can occur, and the result is a disaster.
That's why you won't see this feature in a server, where security is important.
The design of the G5 is fine : it's the best design of the market. Introducing watercooling in a G5 is not serious. It will work 99,9 % of the time without problems, but the 0,1 % problems that will occur, will put Apple in serious problems.
Segway, many people, many people smarter than I, have explained that liquid cooling is ultimately air cooling. Believe them!
Water cooling is NOT air cooling.
Liquid cooling USES AIR cooling... but air cooling does not USE WATER! lol
This argument that liquid cooling uses air is ridiculous. It is just a BS technical argument.
The reality is that water allows you to cool an object faster than ONLY aircooling. Water(and additives) allow MORE heat to be carried away from the object, and carry it away faster. You can also increase the surface area to an infinite extent which you cannot do with a metal heatsink.
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And you would WANT a fan. The good thing about fans is that they give you control over the heat removal. Variable speed.
A water cooling system can be controlled, auto cooling systems do this.
I disagree with this.... IMO water cooling can be acheived without fans... the question is would people pay the extra money for a totally silent computer and deal with the larger radiator and/or water resevoir it would require? I would... but I could see others not wanting to.
The Popular Mechanics article mentions a price of $5000-$6000. That's all I can say.
[...]A water cooling system can be controlled, auto cooling systems do this.
An auto's cooling system relies on moving the heat from inside the engine to the radiator, where moving air transfers the heat to the outside of the car. When sitting at idle--when no air moves past the radiator due to motion--the engine thermostat will enable a fan to blow across the radiator. If this fan does not engage, your car will overheat.
I understand your passion for liquid cooling--it is cool, after all --but please accept the simple fact that a liquid cooling system only *moves* (and, in fact generates additional) heat to a location more convenient to dissipate it into the air. My pismo has a liquid-filled heat pipe to move heat from the processor to the aluminum heat sink near the fan--so Apple *does* use liquid cooling where it makes sense. In this case, the heat itself is the mechanism to cause the liquid to move through the pipe--no pump is needed.
Any cooling system--whether radiative, liquid or thermoelectric (Peltier junction)--has the singular goal of moving heat from one place to another, usually the outside air. At that final interface, you must move air across a large surface area (vanes on a radiator, etc.) to dissipate the heat. If the heat is not removed quickly enough from, say, a liquid cooling system, the temperature of the liquid will rise and reach an equilibrium of heat generation (processors, etc.) and heat removal (radiation/convection) If that equilibrium temperature is higher than the max junction temp of any device in the cooling chain, the system fails. Also, a problem with any active cooling system is that it will actually generate heat in the process, requiring a larger dissipative surface or more lfm (Linear Feet/Minute) of air. A refrigerator with its door open will *heat* your kitchen, not cool it. Similarly, without proper air-cooling somewhere in the system, a liquid cooler will heat your computer, not cool it.
In my 8 years in industry as an electrical engineer--designing far hotter circuitry than anything inside a PC case--I have only seen active cooling used *once.* We had a fiber optic laser designed to drive 50KM of fiber (SONET Long Reach). This laser used a Peltier Junction to suck the heat out of the laser chip because there was no way to attach a passive heat sink to such a small area (MUCH smaller than a CPU die, btw). On the hot side of the thermoelectric cooler was a *MASSIVE* passive aluminum heat sink--the goal was to pipe the heat from the laser die to a location where it could be dissipated into the air effectively.
The fact is, liquid cooling makes perfect sense when you have heat in inaccessible places (such as inside an engine or a buried chip in a laptop) that can be more efficiently dissipated at a different location--in this case, the heat can be moved to a more convenient place. At that point, however, air cooling *always* takes over--with a radiator, vaned heat sink, etc. And if that dissipating device is not large enough to naturally convect or radiate the heat into the surrounding air, a fan must be used (or the dissipator must move through the air, as the radiator in a car) And... this dissipating device will need to be *larger* than the total area of the internal passive heat sinks replaced by the active cooling system, because it now must remove all of the heat from the devices as well as the heat generated by the active cooler itself! (a car engine will generate more heat to power the water pump to cool itself!)
None of this will stop companies from selling liquid cooling systems, of course, as long as there is a market (right or wrong) for them. They are undeniably cool to see, and possess a "geek factor" which will keep them selling. They are generally not, however, a practical engineering solution to the problem in *most* cases. (not all, as I have mentioned in the above example with the long-reach SONET laser)
As for that PM article you mention--there is not doubt that the system works, and it does keep the system cooler than traditional cooling. But to what end? They mention that the life of the processor will increase, but that is not necessarily true if the traditional method keeps the junction temperature under ~75% of its rated maximum (i.e. don't believe everything you read)--and it added over $200 to the cost of the PC. I'm not sure I care if my processor lasts 20 years instead of 10, if it ends up in the trash after 5 years. PM has always latched onto cool tech that isn't necessarily practical. Also, if you look at the pictures, there are still passive heat sinks on some of the chips, so there *still* must be a traditional fan on that computer! Unless you want to water cool the entire board, you still need traditional cooling for the other chips on the board! The "chiller" uses a peltier junction (VERY inefficient), so it must be dissipating much more heat than it removes from the chips--the article says that it uses a heat sink and a fan (i.e. air cooling) which is described as "relatively quiet." So, since the existing fan remains in the computer to cool the other circuitry, you have, in fact, *added* fans (and noise) to this system. The goal of this device is not silence.
Hey, I think this stuff is cool, too! They're just not practical or cost effective now. In fact, from an engineering standpoint, they are currently unnecessary in most cases. Now, in a few years when a processor module generates 300W in a few square centimeters... you might start to see some more fancy solutions--then you can resurrect this thread again and serve us all a nice fat helping of crow!
I do think this stuff is interesting... but that isn't really why I keep harping on this. I really respect Apples design work. I even admire the design work of this fan system... but I feel like Apple "punked out". They had to make a decision about how they were going to address heat issues, now and in the near future and this decision seems like the absolute wrong direction to me. I guess I am just more disappointed than anything... I expected a step forward with the G5 in terms of design... this is like a step sideways.
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fact, from an engineering standpoint, they are currently unnecessary in most cases.
When a computer is made LARGER than the previous model and has LESS internal expandability and STILL isn't silent there is something wrong IMO.
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Now, in a few years when a processor module generates 300W in a few square centimeters... you might start to see some more fancy solutions--then you can resurrect this thread again and serve us all a nice fat helping of crow!
My point is that that time is already here... for the reasons I have mentioned.
Maybe this is all just part of a marketing gimmick. Maybe the "wind tunnel" was just ONE step in Apple's "heat wars". lol
In the mean time... here is a sampling of crow: :P
With this liquid-cooling system, in principle, computers would be able to run without a fan.
Computer sales may be cooling, but computer chips keep getting hotter, and an innovative new way to cool them uses liquid forced through micro-channels only three times the width of a human hair.
The new system may be arriving just in time -- in three years, analysts expect microprocessor chips will generate four times more heat than chips in today's personal computers.
A "pump-less" liquid-cooling system for tomorrow's computers is the brainchild of Purdue University researchers Issam Mudawar and Swaraj Mukherjee.
"Whereas current high-performance chips generate about 75 watts per square centimeter, chips in the near future will generate more than 300 watts per square centimeter," Mudawar told NewsFactor. "Any time you squeeze more circuitry into the same space, you are producing more heat per unit area and per unit volume," he added.
Tiny Bubbles Are Just Fine
The Purdue system solves two problems. Researchers previously thought bubbles might block the circulation of liquid forced to flow through such small channels. Engineers also thought electric pumps might be needed to push liquid through the narrow channels, increasing the cooling system's cost and complexity while potentially decreasing its reliability.
Instead, the two Purdue engineers discovered that liquid flows through a micro-tube easily because the bubbles are much smaller than the diameter of the tube.
"We were surprised to see that the liquid forms really miniature bubbles, so they slip through really fast," Mudawar said. "The bubbles don't block the flow, as you would expect."
The system also uses a closed-loop design that negates the need for a pump -- the liquid circulates in a self-sustaining flow that carries heat away from the computer chip .
"This new cooling method, if it can work in a reliable way for at least 50,000 hours, can certainly be a big help in electronics," said Texas A&M electrical engineering professor Laszlo Kish, a prominent expert in the field of microchip heat and power dissipation.
Fanning the Future
Presently, computers use fans and heat sinks to cool circuitry -- technology that "will not be efficient enough to remove the increasing heat generated by future chips," Mudawar said.
Chip and computer manufacturers are aware of the pending problem.
"Microprocessor makers are making strong efforts to avoid further increases in power dissipation and heat generation," Kish told NewsFactor. "For example, they are trying to design circuitry which switches off those parts of the processor not currently in use."
Efforts to reduce power loss as heat energy probably will not be enough -- hence the need for a new type of coolant.
In the fluid-cooling system, a dielectric liquid -- a liquid that does not conduct electricity -- flows through micro-channels in a metal plate touching the chip. The chip heats the liquid, producing bubbles of vapor that rise in one of two vertical, parallel tubes. At the top of the tube, a fan cools and condenses the vapor, which flows back into the tube and descends, creating a self-sustaining flow that eventually re-enters the micro-channel plate, starting the process again.
"With this liquid-cooling system , in principle, computers would be able to run without a fan , and everybody would be happy about that," Kish said. "I applaud this new discovery, and I think the physics behind it is interesting for further studies."
And here is an interesting message from an engineer in that same thread...
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water next to precious servers, well, on that note, my server is watercooled. i heard a while back one company did it for one of their servers. imean, a mainframe server... i think it was HP. As for that palestine note, im not in palestine as a matter of fact.. sorry for saying that, just an impulse... i work for IBM middle east based in dubai.. however, i get shipped to palestine every now and then for r&d... im sure you are aware guru that when i refer to palestine, i mean all of it... sorry, us sandmonkeys are still living 50 years in the past...
Back to topic.. i understand your fears of introducing water into your machine, but you should do a little reaserch and you will see its not dangerous if you do your shit right.. I know, the first time for me was scary, and i did infact suceed in designing a fountain that cost me 1500$ in parts... but i did learn from it.. (i learnt you should handle your epoxy like you handle your condoms, never buy them unless you are sure they are original)... but i mean, ofcourse a lot of testing and percautions are involved. I just dont know whether NEC took those kinds of percautions.. But it seems like that system was pritty inline (no resevour) so i wouldent worry unless they didnt thread and tape their connections properly.. If you guys are interested in WC look at www.overclockers.com , thats wher i started and thats where everybody starts....
Personally, i would encourage WC not because its better (which it is) but its really fun research reading those articles, it has a lot of hands on (im a mech engineer from Virginia Tech) that interests me... the experimentation is fun and in the end, your machine runs cool and quite and very very much overclocked. In lan parties, WC and OCed machines demand respect, and more often than not they do over modded cases. I guess it comes from being a student and having to sleep in the same room as your pc...
I think iSegway's argument is misplaced. What he really is compaining about is that the G5 case should be smaller, in his estimation. Whether or not the case size is really an issue to other people, is another issue. If it isn't, then the argument that water-cooling is really necessary falls apart. So the only issue left is for iSegway to argue that the case needs to be smaller or the world will end (which I'm pretty sure it won't).
...and for the record- yes, a water-cooled system is essentially an air-cooled system at the very end of the chain (unless he would like to argue that the heat is somehow channeled into a magic black box, never to be seen again). Thus it will be susceptible to all the caveats that he has saw fit to ding air-cooled setups for. Most of all, you can be sure that a water-cooled system will not be more "efficient" than an air-cooled system. By it's very nature, the water-cooled system relies on an air-cooled system at the very end of the chain to truly work. Thus the efficiency will be a composite of 2 systems. Whereas the efficiency of an air-cooled system will simply be that of a single system- itself.
The bottomline is that water-cooling offers unique capabilities when the situation arises. However, if the same job can be done with air-cooling (within acceptable tolerances), then there is very little argument to be had that WC is automatically "better".
It's popular for 3rd party CPU upgrades on the PC side of things because it has the "geek marketing" factor behind it. That and it offers an additional degree of freedom for DIY'ers who love to overclock the piss out of CPU's which already run pretty hot just at the stock clockrate. It's easier to pull-off once you have massive overkill at your disposal. However, if you have an engineering team with expertises to design an acceptable heatsink for a CPU (as in an engineered, 1st party product), there is nothing wrong with that.
Let me guess... you are one of these dreaded "Mac apologists"... am I right?
Just try to remember that a critique of Apples choice in design is not a personal attack on YOU. So there is really no need to attack me personally.
Uhh, no? Just setting you straight.
The fact you come up with a response like that, with those particular notions speaks volumes about what you are trying to do here.
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What is it at the beginning? lol
By all means, it is water-cooled. However, you continue to ignore what it has to revert to at the end of the chain. Thus all the bad qualities you cite for air-cooling are inherently present for water-cooling. If you insist that water-cooling is superior, while ignoring that little part at the very end, then what is the point? You could argue that gasoline engines are pollution free if you ignore the exhaust pipe, right?
The fact you come up with a response like that, with those particular notions speaks volumes about what you are trying to do here.
That is called paranoia dude. I am not trolling. This is something that I find very interesting. Like I said... I really was disappointed that Apple didn't do something more inspired to deal with the heat issues. This just seems like a bandaid for the problem... not a long term solution.
I think the Cube really made me expect more. I do not want to fight... I just wish others would have a bit more of an open mind.
Just notice that I have gotten many more "it's impossible to make a better cooling system" than I have had people show me possible new directions for cooling solutions. I think that says a lot about what is going on here.
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By all means, it is water-cooled. However, you continue to ignore what it has to revert to at the end of the chain. Thus all the bad qualities you cite for air-cooling are inherently present for water-cooling.
Have you been reading the things I post? I have shown you possible systems that don't require pumps or fans.
Also... as I have stated many times... a radiator can be made to disperse heat MUCH better than just a metal heat sink. That is something a PURELY air cooled system cannot do. Also.. water... and many other liquids can absorb and remove heat more quickly than AIR.
Perhaps, they aren't misguided? Clearly, you refuse to acknowledge them because it collapses your argument. So where do you think that heat goes, after the water has absorbed it? This ought to be a hoot...
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That is called paranoia dude. I am not trolling. This is something that I find very interesting.
It was not wise of you to bring up terms like "dreaded Mac apologist" and "personal attacks" then, to build your "I'm not a troll" case. Was it?
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I just wish others would have a bit more of an open mind.
An open mind, or just somebody who unquestioningly agrees with you (which would not be open-minded of you, now would it?). Clearly there are equally persuasive arguments against as there are for. Perhaps, it is time for you to consider these aren't just "misguided arguments" to a question that must "only" have one correct answer?
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Just notice that I have gotten amny more "is impossible to make a better cooling system" than I have had people show me possible new directions for cooling solutions. I think that says a lot about what is going on here.
Your intent was not to discuss alternative cooling solutions- just that water-cooling is the right answer, period. Air and water are pretty much the mainstay approaches. What else were you expecting? ...to talk about Peltiers?
Have you been reading the things I post? I have shown you possible systems that don't require pumps or fans.
This won't make them any much less reliant on air-cooling as part of the system. W/o pumps and fans you've pretty much annihilated all claims of high-efficiency and high-dissipation, as well. So which is it you are really interested in- inefficient, small-scale water-cooling that is quiet or efficient, high-capacity water cooling that uses pumps and fans?
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Also... as I have stated many times... a radiator can be made to disperse heat MUCH better than just a metal heat sink.
...not w/o a pump and some decent flowrate, it won't.
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That is something a PURELY air cooled system cannot do.
A radiator wouldn't rely on air-cooling, now would it?
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Also.. water... and many other liquids can absorb and remove heat more quickly than AIR.
You keep ignoring that at some point the heat in the liquid must invariably make the jump to air. Thus that will be your limiting factor, water or not, oil or not, liquid or not. Using your logic, you could just argue that an infinitely large block of copper would be the ultimate heat sink because its thermal qualities trump all liquids by an order of magnitude, it doesn't rely on air-cooling, it would be quiet as a block of copper, and it has zero moving parts. How do ya like dem Apples?
You keep ignoring that at some point the heat in the liquid must invariably make the jump to air. Thus that will be your limiting factor, water or not, oil or not, liquid or not.
So this is how you want it hunh?
I must have really hit a nerve.
You have ZERO argument for the actual point being discussed... the only thing you can argue is that the heat will eventually be dispersed into air. lol
Congratulations. Well done. Quite the problem solver you are. Bravo. You have saved the Mac name.
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You keep ignoring that at some point the heat in the liquid must invariably make the jump to air. Thus that will be your limiting factor, water or not, oil or not, liquid or not.
Yes... Bravo... you are a genius.
Well done. What a fool I am! Water cooling cannot possibly be more efficient to cool your computer quietly BECAUSE that heat will eventually be transmitted to air!
You have ZERO argument for the actual point being discussed... the only thing you can argue is that the heat will eventually be dispersed into air. lol
It's not about hitting a nerve. It's just reality, served on a plate for you. Enjoy!
So which is it- do you agree or disagree with the statement? ...or refuse to answer?
Seriously, would you argue that a single transistor clocked to 10 GHz would make the ultimate CPU, if you could just ignore that its output has absolutely no potential for any kind of logical computation?
Well done. What a fool I am! Water cooling cannot possibly be more efficient to cool your computer quietly BECAUSE that heat will eventually be transmitted to air!
My guess is that you simply lack an understanding of the physics involved to truly appreciate the relevance of that statement. If you can argue the foibles of air-cooling, then how can you argue that water-cooling will be better when it relies on air-cooling ultimately to work? It's a system, right? Taking just a part of the system and heralding its advantages is pointless.
The thing you have to realize is that all desktop computers right now are air-cooled (even if there is a sticker on the case that says otherwise). Yours just has a water-cooling step added in the chain. Really, you shouldn't be ashamed of it or opposed to the notion. It's just reality and physics.
Just answer me this, Randycat99, If I have no valuable point and have no understanding of the situation and can't possibly understand the physics involved... then why are you wasting your time arguing with me?
Just answer me this, Randycat99, If I have no valuable point...
It's a valid point in specific situations. It is just a bit misguided when you attempt to apply it universally.
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...and have no understanding of the situation and can't possibly understand the physics involved...
I'm sure you could endeavor to figure it out if you did more research with an open mind. Question is, will you?
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then why are you wasting your time arguing with me?
Actually, I'm doing the "correcting". You are doing the arguing, evidently. The opportunity to give additional clarification for the benefit of this topic on this board was worthwhile to me. I do give full credit to other posters here that preceded me, however, as they were certainly well on their way to addressing your points in an appropriate manner. I only reiterated and gave some additional examples.
Comments
Well... servers don't share space with people in their living environments.... but this brings up an interesting point... do we have to have our computers in the immediate area where we use them?
I am not very computer savvy... I feel confident that watercooling is superior to air cooling because this is a subject that I have researched quite a bit. But... that doesn't mean their isn't a better solution even than watercooling.
Let's say that we store the bulk of the computer in a different location? What problems might this pose? Will there be performance losses doing this? Could this be done wirelessly? This would be ideal because wiring would be a problem.
Could you use pre-existing home wiring as the communication lines between the "home server" and the pieces you would need to work with(optical drives keyboard and monitor)?
Segway, many people, many people smarter than I, have explained that liquid cooling is ultimately air cooling. Believe them! I mean, where does the heat go after it goes from the processor to the liquid? Does it just disappear? Unless you had the computer connect to a lake or river it has to pass to the air.
And you would WANT a fan. The good thing about fans is that they give you control over the heat removal. Variable speed. Slowly, quietly running most of the time but the capacity to buzz if your wife puts a book right in front of the vent.
However, a fan with water cooling does not mean fewer, noisier fans than in air cooling. Why? Cause the radiator/heat sink is more efficient in liquid. A metal heatsink has heat passively conducting its way through. A radiator has the hot liquid pushed to all parts. So equal heat is spread over a larger area and you know the rest.
Notice the vanes(?) are slimmer and more numerous on a radiator vs. heatsink? In a heatsink why bother, you have to start with thick vanes to have enough material (copper or aluminum) to carry all that heat. And even if the sink branched out like an oak tree the heat travels too slowly to reach the final twigs to be worth the trouble. Also, the heat sink would resemble a tree in size too!
In the meantime, Apple has done a wonderful job with controlled fans in the G5. Ive heard a G5. But just barely.
That's why you won't see this feature in a server, where security is important.
The design of the G5 is fine : it's the best design of the market. Introducing watercooling in a G5 is not serious. It will work 99,9 % of the time without problems, but the 0,1 % problems that will occur, will put Apple in serious problems.
Segway, many people, many people smarter than I, have explained that liquid cooling is ultimately air cooling. Believe them!
Water cooling is NOT air cooling.
Liquid cooling USES AIR cooling... but air cooling does not USE WATER! lol
This argument that liquid cooling uses air is ridiculous. It is just a BS technical argument.
The reality is that water allows you to cool an object faster than ONLY aircooling. Water(and additives) allow MORE heat to be carried away from the object, and carry it away faster. You can also increase the surface area to an infinite extent which you cannot do with a metal heatsink.
And you would WANT a fan. The good thing about fans is that they give you control over the heat removal. Variable speed.
A water cooling system can be controlled, auto cooling systems do this.
Its more of a "wow" factor to impress fellow geeks.
Originally posted by iSegway
I disagree with this.... IMO water cooling can be acheived without fans... the question is would people pay the extra money for a totally silent computer and deal with the larger radiator and/or water resevoir it would require? I would... but I could see others not wanting to.
The Popular Mechanics article mentions a price of $5000-$6000. That's all I can say.
Originally posted by iSegway
[...]A water cooling system can be controlled, auto cooling systems do this.
An auto's cooling system relies on moving the heat from inside the engine to the radiator, where moving air transfers the heat to the outside of the car. When sitting at idle--when no air moves past the radiator due to motion--the engine thermostat will enable a fan to blow across the radiator. If this fan does not engage, your car will overheat.
I understand your passion for liquid cooling--it is cool, after all
Any cooling system--whether radiative, liquid or thermoelectric (Peltier junction)--has the singular goal of moving heat from one place to another, usually the outside air. At that final interface, you must move air across a large surface area (vanes on a radiator, etc.) to dissipate the heat. If the heat is not removed quickly enough from, say, a liquid cooling system, the temperature of the liquid will rise and reach an equilibrium of heat generation (processors, etc.) and heat removal (radiation/convection) If that equilibrium temperature is higher than the max junction temp of any device in the cooling chain, the system fails. Also, a problem with any active cooling system is that it will actually generate heat in the process, requiring a larger dissipative surface or more lfm (Linear Feet/Minute) of air. A refrigerator with its door open will *heat* your kitchen, not cool it. Similarly, without proper air-cooling somewhere in the system, a liquid cooler will heat your computer, not cool it.
In my 8 years in industry as an electrical engineer--designing far hotter circuitry than anything inside a PC case--I have only seen active cooling used *once.* We had a fiber optic laser designed to drive 50KM of fiber (SONET Long Reach). This laser used a Peltier Junction to suck the heat out of the laser chip because there was no way to attach a passive heat sink to such a small area (MUCH smaller than a CPU die, btw). On the hot side of the thermoelectric cooler was a *MASSIVE* passive aluminum heat sink--the goal was to pipe the heat from the laser die to a location where it could be dissipated into the air effectively.
The fact is, liquid cooling makes perfect sense when you have heat in inaccessible places (such as inside an engine or a buried chip in a laptop) that can be more efficiently dissipated at a different location--in this case, the heat can be moved to a more convenient place. At that point, however, air cooling *always* takes over--with a radiator, vaned heat sink, etc. And if that dissipating device is not large enough to naturally convect or radiate the heat into the surrounding air, a fan must be used (or the dissipator must move through the air, as the radiator in a car) And... this dissipating device will need to be *larger* than the total area of the internal passive heat sinks replaced by the active cooling system, because it now must remove all of the heat from the devices as well as the heat generated by the active cooler itself! (a car engine will generate more heat to power the water pump to cool itself!)
None of this will stop companies from selling liquid cooling systems, of course, as long as there is a market (right or wrong) for them. They are undeniably cool to see, and possess a "geek factor" which will keep them selling. They are generally not, however, a practical engineering solution to the problem in *most* cases. (not all, as I have mentioned in the above example with the long-reach SONET laser)
As for that PM article you mention--there is not doubt that the system works, and it does keep the system cooler than traditional cooling. But to what end? They mention that the life of the processor will increase, but that is not necessarily true if the traditional method keeps the junction temperature under ~75% of its rated maximum (i.e. don't believe everything you read)--and it added over $200 to the cost of the PC. I'm not sure I care if my processor lasts 20 years instead of 10, if it ends up in the trash after 5 years. PM has always latched onto cool tech that isn't necessarily practical. Also, if you look at the pictures, there are still passive heat sinks on some of the chips, so there *still* must be a traditional fan on that computer! Unless you want to water cool the entire board, you still need traditional cooling for the other chips on the board! The "chiller" uses a peltier junction (VERY inefficient), so it must be dissipating much more heat than it removes from the chips--the article says that it uses a heat sink and a fan (i.e. air cooling) which is described as "relatively quiet." So, since the existing fan remains in the computer to cool the other circuitry, you have, in fact, *added* fans (and noise) to this system. The goal of this device is not silence.
Hey, I think this stuff is cool, too!
Hey, I think this stuff is cool, too!
I do think this stuff is interesting... but that isn't really why I keep harping on this. I really respect Apples design work. I even admire the design work of this fan system... but I feel like Apple "punked out". They had to make a decision about how they were going to address heat issues, now and in the near future and this decision seems like the absolute wrong direction to me. I guess I am just more disappointed than anything... I expected a step forward with the G5 in terms of design... this is like a step sideways.
fact, from an engineering standpoint, they are currently unnecessary in most cases.
When a computer is made LARGER than the previous model and has LESS internal expandability and STILL isn't silent there is something wrong IMO.
Now, in a few years when a processor module generates 300W in a few square centimeters... you might start to see some more fancy solutions--then you can resurrect this thread again and serve us all a nice fat helping of crow!
My point is that that time is already here... for the reasons I have mentioned.
Maybe this is all just part of a marketing gimmick. Maybe the "wind tunnel" was just ONE step in Apple's "heat wars". lol
In the mean time... here is a sampling of crow: :P
Article
Pumps, Not Fans, May Cool Tomorrow's Computers
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By Mike Martin
NewsFactor Network
May 9, 2003
With this liquid-cooling system, in principle, computers would be able to run without a fan.
Computer sales may be cooling, but computer chips keep getting hotter, and an innovative new way to cool them uses liquid forced through micro-channels only three times the width of a human hair.
The new system may be arriving just in time -- in three years, analysts expect microprocessor chips will generate four times more heat than chips in today's personal computers.
A "pump-less" liquid-cooling system for tomorrow's computers is the brainchild of Purdue University researchers Issam Mudawar and Swaraj Mukherjee.
"Whereas current high-performance chips generate about 75 watts per square centimeter, chips in the near future will generate more than 300 watts per square centimeter," Mudawar told NewsFactor. "Any time you squeeze more circuitry into the same space, you are producing more heat per unit area and per unit volume," he added.
Tiny Bubbles Are Just Fine
The Purdue system solves two problems. Researchers previously thought bubbles might block the circulation of liquid forced to flow through such small channels. Engineers also thought electric pumps might be needed to push liquid through the narrow channels, increasing the cooling system's cost and complexity while potentially decreasing its reliability.
Instead, the two Purdue engineers discovered that liquid flows through a micro-tube easily because the bubbles are much smaller than the diameter of the tube.
"We were surprised to see that the liquid forms really miniature bubbles, so they slip through really fast," Mudawar said. "The bubbles don't block the flow, as you would expect."
The system also uses a closed-loop design that negates the need for a pump -- the liquid circulates in a self-sustaining flow that carries heat away from the computer chip .
"This new cooling method, if it can work in a reliable way for at least 50,000 hours, can certainly be a big help in electronics," said Texas A&M electrical engineering professor Laszlo Kish, a prominent expert in the field of microchip heat and power dissipation.
Fanning the Future
Presently, computers use fans and heat sinks to cool circuitry -- technology that "will not be efficient enough to remove the increasing heat generated by future chips," Mudawar said.
Chip and computer manufacturers are aware of the pending problem.
"Microprocessor makers are making strong efforts to avoid further increases in power dissipation and heat generation," Kish told NewsFactor. "For example, they are trying to design circuitry which switches off those parts of the processor not currently in use."
Efforts to reduce power loss as heat energy probably will not be enough -- hence the need for a new type of coolant.
In the fluid-cooling system, a dielectric liquid -- a liquid that does not conduct electricity -- flows through micro-channels in a metal plate touching the chip. The chip heats the liquid, producing bubbles of vapor that rise in one of two vertical, parallel tubes. At the top of the tube, a fan cools and condenses the vapor, which flows back into the tube and descends, creating a self-sustaining flow that eventually re-enters the micro-channel plate, starting the process again.
"With this liquid-cooling system , in principle, computers would be able to run without a fan , and everybody would be happy about that," Kish said. "I applaud this new discovery, and I think the physics behind it is interesting for further studies."
More pictures at this addresss: http://8ballshardware.com/forums/viewtopic.php?t=512
And here is an interesting message from an engineer in that same thread...
water next to precious servers, well, on that note, my server is watercooled. i heard a while back one company did it for one of their servers. imean, a mainframe server... i think it was HP. As for that palestine note, im not in palestine as a matter of fact.. sorry for saying that, just an impulse... i work for IBM middle east based in dubai.. however, i get shipped to palestine every now and then for r&d... im sure you are aware guru that when i refer to palestine, i mean all of it... sorry, us sandmonkeys are still living 50 years in the past...
Back to topic.. i understand your fears of introducing water into your machine, but you should do a little reaserch and you will see its not dangerous if you do your shit right.. I know, the first time for me was scary, and i did infact suceed in designing a fountain that cost me 1500$ in parts... but i did learn from it.. (i learnt you should handle your epoxy like you handle your condoms, never buy them unless you are sure they are original)... but i mean, ofcourse a lot of testing and percautions are involved. I just dont know whether NEC took those kinds of percautions.. But it seems like that system was pritty inline (no resevour) so i wouldent worry unless they didnt thread and tape their connections properly.. If you guys are interested in WC look at www.overclockers.com , thats wher i started and thats where everybody starts....
Personally, i would encourage WC not because its better (which it is) but its really fun research reading those articles, it has a lot of hands on (im a mech engineer from Virginia Tech) that interests me... the experimentation is fun and in the end, your machine runs cool and quite and very very much overclocked. In lan parties, WC and OCed machines demand respect, and more often than not they do over modded cases. I guess it comes from being a student and having to sleep in the same room as your pc...
...and for the record- yes, a water-cooled system is essentially an air-cooled system at the very end of the chain (unless he would like to argue that the heat is somehow channeled into a magic black box, never to be seen again). Thus it will be susceptible to all the caveats that he has saw fit to ding air-cooled setups for. Most of all, you can be sure that a water-cooled system will not be more "efficient" than an air-cooled system. By it's very nature, the water-cooled system relies on an air-cooled system at the very end of the chain to truly work. Thus the efficiency will be a composite of 2 systems. Whereas the efficiency of an air-cooled system will simply be that of a single system- itself.
The bottomline is that water-cooling offers unique capabilities when the situation arises. However, if the same job can be done with air-cooling (within acceptable tolerances), then there is very little argument to be had that WC is automatically "better".
It's popular for 3rd party CPU upgrades on the PC side of things because it has the "geek marketing" factor behind it. That and it offers an additional degree of freedom for DIY'ers who love to overclock the piss out of CPU's which already run pretty hot just at the stock clockrate. It's easier to pull-off once you have massive overkill at your disposal. However, if you have an engineering team with expertises to design an acceptable heatsink for a CPU (as in an engineered, 1st party product), there is nothing wrong with that.
Let me guess... you are one of these dreaded "Mac apologists"... am I right?
Just try to remember that a critique of Apples choice in design is not a personal attack on YOU. So there is really no need to attack me personally.
BTW...
...and for the record- yes, a water-cooled system is essentially an air-cooled system at the very end
What is it at the beginning? lol
Originally posted by iSegway
Did I strike a nerve, Randycat99? lol
Let me guess... you are one of these dreaded "Mac apologists"... am I right?
Just try to remember that a critique of Apples choice in design is not a personal attack on YOU. So there is really no need to attack me personally.
Uhh, no? Just setting you straight.
The fact you come up with a response like that, with those particular notions speaks volumes about what you are trying to do here.
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What is it at the beginning? lol
By all means, it is water-cooled. However, you continue to ignore what it has to revert to at the end of the chain. Thus all the bad qualities you cite for air-cooling are inherently present for water-cooling. If you insist that water-cooling is superior, while ignoring that little part at the very end, then what is the point? You could argue that gasoline engines are pollution free if you ignore the exhaust pipe, right?
Uhh, no? Just setting you straight.
By repeating other peoples misguided arguments?
The fact you come up with a response like that, with those particular notions speaks volumes about what you are trying to do here.
That is called paranoia dude. I am not trolling. This is something that I find very interesting. Like I said... I really was disappointed that Apple didn't do something more inspired to deal with the heat issues. This just seems like a bandaid for the problem... not a long term solution.
I think the Cube really made me expect more. I do not want to fight... I just wish others would have a bit more of an open mind.
Just notice that I have gotten many more "it's impossible to make a better cooling system" than I have had people show me possible new directions for cooling solutions. I think that says a lot about what is going on here.
By all means, it is water-cooled. However, you continue to ignore what it has to revert to at the end of the chain. Thus all the bad qualities you cite for air-cooling are inherently present for water-cooling.
Have you been reading the things I post? I have shown you possible systems that don't require pumps or fans.
Also... as I have stated many times... a radiator can be made to disperse heat MUCH better than just a metal heat sink. That is something a PURELY air cooled system cannot do. Also.. water... and many other liquids can absorb and remove heat more quickly than AIR.
Great site
Originally posted by iSegway
By repeating other peoples misguided arguments?
Perhaps, they aren't misguided? Clearly, you refuse to acknowledge them because it collapses your argument. So where do you think that heat goes, after the water has absorbed it? This ought to be a hoot...
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That is called paranoia dude. I am not trolling. This is something that I find very interesting.
It was not wise of you to bring up terms like "dreaded Mac apologist" and "personal attacks" then, to build your "I'm not a troll" case. Was it?
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I just wish others would have a bit more of an open mind.
An open mind, or just somebody who unquestioningly agrees with you (which would not be open-minded of you, now would it?). Clearly there are equally persuasive arguments against as there are for. Perhaps, it is time for you to consider these aren't just "misguided arguments" to a question that must "only" have one correct answer?
Quote:
Just notice that I have gotten amny more "is impossible to make a better cooling system" than I have had people show me possible new directions for cooling solutions. I think that says a lot about what is going on here.
Your intent was not to discuss alternative cooling solutions- just that water-cooling is the right answer, period. Air and water are pretty much the mainstay approaches. What else were you expecting? ...to talk about Peltiers?
Originally posted by iSegway
Have you been reading the things I post? I have shown you possible systems that don't require pumps or fans.
This won't make them any much less reliant on air-cooling as part of the system. W/o pumps and fans you've pretty much annihilated all claims of high-efficiency and high-dissipation, as well. So which is it you are really interested in- inefficient, small-scale water-cooling that is quiet or efficient, high-capacity water cooling that uses pumps and fans?
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Also... as I have stated many times... a radiator can be made to disperse heat MUCH better than just a metal heat sink.
...not w/o a pump and some decent flowrate, it won't.
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That is something a PURELY air cooled system cannot do.
A radiator wouldn't rely on air-cooling, now would it?
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Also.. water... and many other liquids can absorb and remove heat more quickly than AIR.
You keep ignoring that at some point the heat in the liquid must invariably make the jump to air. Thus that will be your limiting factor, water or not, oil or not, liquid or not. Using your logic, you could just argue that an infinitely large block of copper would be the ultimate heat sink because its thermal qualities trump all liquids by an order of magnitude, it doesn't rely on air-cooling, it would be quiet as a block of copper, and it has zero moving parts. How do ya like dem Apples?
You keep ignoring that at some point the heat in the liquid must invariably make the jump to air. Thus that will be your limiting factor, water or not, oil or not, liquid or not.
So this is how you want it hunh?
I must have really hit a nerve.
You have ZERO argument for the actual point being discussed... the only thing you can argue is that the heat will eventually be dispersed into air. lol
Congratulations. Well done. Quite the problem solver you are. Bravo. You have saved the Mac name.
You keep ignoring that at some point the heat in the liquid must invariably make the jump to air. Thus that will be your limiting factor, water or not, oil or not, liquid or not.
Yes... Bravo... you are a genius.
Well done. What a fool I am! Water cooling cannot possibly be more efficient to cool your computer quietly BECAUSE that heat will eventually be transmitted to air!
How could I have missed it!
BRAVO!
LOL
Originally posted by iSegway
So this is how you want it hunh?
I must have really hit a nerve.
You have ZERO argument for the actual point being discussed... the only thing you can argue is that the heat will eventually be dispersed into air. lol
It's not about hitting a nerve. It's just reality, served on a plate for you. Enjoy!
So which is it- do you agree or disagree with the statement? ...or refuse to answer?
Seriously, would you argue that a single transistor clocked to 10 GHz would make the ultimate CPU, if you could just ignore that its output has absolutely no potential for any kind of logical computation?
Originally posted by iSegway
Well done. What a fool I am! Water cooling cannot possibly be more efficient to cool your computer quietly BECAUSE that heat will eventually be transmitted to air!
My guess is that you simply lack an understanding of the physics involved to truly appreciate the relevance of that statement. If you can argue the foibles of air-cooling, then how can you argue that water-cooling will be better when it relies on air-cooling ultimately to work? It's a system, right? Taking just a part of the system and heralding its advantages is pointless.
The thing you have to realize is that all desktop computers right now are air-cooled (even if there is a sticker on the case that says otherwise). Yours just has a water-cooling step added in the chain. Really, you shouldn't be ashamed of it or opposed to the notion. It's just reality and physics.
Originally posted by iSegway
Just answer me this, Randycat99, If I have no valuable point...
It's a valid point in specific situations. It is just a bit misguided when you attempt to apply it universally.
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...and have no understanding of the situation and can't possibly understand the physics involved...
I'm sure you could endeavor to figure it out if you did more research with an open mind. Question is, will you?
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then why are you wasting your time arguing with me?
Actually, I'm doing the "correcting". You are doing the arguing, evidently. The opportunity to give additional clarification for the benefit of this topic on this board was worthwhile to me. I do give full credit to other posters here that preceded me, however, as they were certainly well on their way to addressing your points in an appropriate manner. I only reiterated and gave some additional examples.