iSegway, the reason for so many fans isn't due to high CPU temperatures, it's for low noise. It's quieter to run many fans slowley than to run a few fans quickly. The cooling system in the new Powermacs was designed with low-noise as a primary goal. I don't know how loud a liquid cooling system would be, but with a compressor and fans it might not be any quieter than the current Powermacs.
Then there is the issue of cost and reliability, both of which are affected by the complexity of liquid cooling systems. Fans are cheap and very reliable. Liquid cooling (for computers) costs more, and its reliability is far lower.
If Apple can achieve their design goals for noise and cooling capacity by using fans, there's little incentive to use a more complex and expensive solution.
-52 °C is -61.6 °F. There's not a single freezer that can achieve this. The next step in cooling, after such a compressor, is liquid N2.
Actually that's not true. I work in biomedical research, and we use freezers that achieve temperatures as low as -120? C. Dual compressors are used for -80? C, and quad compressors get down to around -120? C. -80? C freezers are very common, the other's less so because of cost and reliability. Liquid N2 is typically used for anything below -80? C in most labs.
I'd bet that with liquid N2 cooling, Apple could clock the G5 high enough to shut up the x86 whiners.
Are you saying that watercooling isn't superior to air cooling with computers?
Well, duh.
Who wants to spring a leak? The major problem with air cooling is the noise, but 9 computer controlled fans with some amazing ventilation make this a non issue. Each of the 4 compartments within the tower can be independently cooled, meaning that the fans will be on as little as possible and turn as slowly as possible. Apple heard the complaints about the wind tunnel g4's, and I think they've addressed it.
There is more empty space than not in that G5 enclosure. The G5 is bigger than the G4 and has no expandability.
Is it too much to ask to have a case that doesn't fill with dust?
I am going to laugh at all you nay sayers in a few years when water cooling becomes standard.
If I am wrong none of us will be laughing because our computers will will be as large as closets and be almost empty with a screen door type enclosure.
By the way... you are saying that it is more difficult/dangerous/expensive to put a water cooling system in a computer than it is to do this - link another link
-52 °C is -61.6 °F. There's not a single freezer that can achieve this. The next step in cooling, after such a compressor, is liquid N2.
Add dry ice to rubbing alcohol. Let the dry ice cool down the alcohol. As the dry ice sublimes it will make the rubbing alcohol look like sprite, but whatever you do, don't touch the alcohol- you will loose a part of your body. This is a decent intermediate step between a compressor and Liquid N2. Best of all, it doesn't place the same heat (cold) stresses on metal that LN2 can.
My previous comparison to nuclear energy isn't all that strange. The energy density of chips is thought to surpass the energy density of nuclear reactors unless Intel gets its act together with respect to heat. It is a shame that we can't convert infrared radiation directly into electrical energy (yet). Otherwise, you could get some power out of your CPU usage.
Water cooling only works in a closed system when you are using the water to move the heat from the hot thing to a radiator. Water doesn't give up its heat very easily, so you need a large radiator with lots of surface area. If you used a chemical other than water (with a lower specific heat), then you would need a smaller radiator. Some nuclear reactors use liquid sodium instead of water because once liquid, it very quickly absorbs heat. The reason why nuclear reactors do not have closed heat radiators is that there is no good way to dissipate 6000 Megawatts of heat through a radiator- You would need a radiator with many square miles of surface area. The soultion is to just evaporate the water and have an open system where you need more water. Sorry for the nuclear power lesson.
By the way... you are saying that it is more difficult/dangerous/expensive to put a water cooling system in a computer than it is to do this - link another link
Actually, yes. Fuel cells are self-contained and isolated from the rest of the laptop. With water-cooled systems, you're placing the water container (pipes, tubes, whatever) directly against the electronics to be cooled, or at least exposed in the same section of the casing. And they can't be sealed tight (like a fuel cell) because that'll degrade their ability to absorb heat.
With water-cooled systems, you're placing the water container (pipes, tubes, whatever) directly against the electronics to be cooled, or at least exposed in the same section of the casing.
Apples and Oranges.
Isolated, hunh. Interesting. Yea, my design involved just running the water over the unprotected circuitboard.
Funny how fuel systems can be *totally* isolated but not water. Strange.
Apples and oranges... yeah... ok. lol
So let me get this straight. You are telling me that in your opinion there will never be a mass production water cooled personal computer(desktop that is, since there have already been laptops that incorperate water cooling.)?
If there will be be a mass production water cooled computer someday what kind of technological advancement will be necessary?
Hitachi has begun to sell its new water-cooled notebook computer in Japan. The Flora 270W Silent Mode, as it is called, sports a 1.8GHz mobile Pentium 4, 128 MB RAM, 20 GBhHard drive, and a 15-inch TFT screen. The cost of the machine is a mere 341,000 yen (US$2,941).
Interestingly, the notebook uses a patented Hitachi water-cooling system. Flexible tubing is placed over the chips in the machine and water is pumped through them, taking the heat with it. The tubes then run the water into a tank on the back of the TFT screen that is visible and meant to be aesthetically pleasing. Hitachi says that the tank has been made visible just to differentiate the notebooks from other machines, and that it could easily be hidden.
In terms of cooling performance it is on equal terms with air-cooling, but it has the added advantage of being a much quieter solution. Reliability-wise, the solution lasts more than 5 years, the tubing can circulate the solution 20,000 times, and the pump works for more than 44,000 hours. Hitachi offers a three-year guarantee with the machine.
Hitachi started taking orders on Wednesday and can supply to corporate users outside of Japan, although it is undecided into which consumer markets the notebook will be released. Hitachi is also in talks with companies who want to use the system in servers and plasma display devices. As well, Hitachi is pushing for the cooling technology to become an industry standard.[quote]
The specs on that notebook don't exactly make it a nightmare to cool. (Compare the iBook, which spends most of its time running fanless.) The PowerMac has a lot more work to do. Whatever liquid draws off the heat from the CPUs would have to get rid of it fast, because those suckers are hot (97W apiece, they say), and that probably means a big radiator (just like they have now) and fans to keep it cool (just like they have now). The difference would be that with air cooling, Apple can use lots of fans running slowly to cool the components; with water cooling they'd have to have a couple of fans frantically cooling a specific part (the radiator), which would make them louder.
The issue is not as simple as "water cooling is better" or "water cooling is worse." You have to look at the problem, and part of the problem, as Fawkes pointed out, is that water cooling is air cooling. The water just moves the problem around, so the engineering question is whether there's any advantage to doing that. Obviously, what works for a modestly spec'd notebook (for $3K?!) doesn't necessarily work for a high-end tower. Perhaps the Hitachi solution is better for that notebook, and perhaps it's just gimmicky (again, the iBook manages with smart passive cooling and a backup fan). The cooling solution doesn't last as long as a good fan would, or an entirely passive cooling solution.
As an aside, the mention of liquid sodium as a coolant reminded me of when the Superphenix breeder reactor in France had a coolant leak, not quite 20 years ago. It used (and probably still uses) liquid sodium, so the leak turned one room in the plant into a giant, perpetual fireball. Since the reactor's a breeder (self-fueling) it couldn't be shut down quickly or easily, and since the leak was behind a big fireball they couldn't plug it easily. Now there is an engineering challenge! (The last I heard they were pumping sodium in as fast as it was leaking out, but I can't imagine that was the permanent solution.)
The difference would be that with air cooling, Apple can use lots of fans running slowly to cool the components; with water cooling they'd have to have a couple of fans frantically cooling a specific part (the radiator), which would make them louder.
No you wouldn't. This is absolutely wrong.
Quote:
The issue is not as simple as "water cooling is better" or "water cooling is worse." You have to look at the problem, and part of the problem, as Fawkes pointed out, is that water cooling is air cooling.
No! Water cooling is not air cooling. Air cooling is air cooling. Water cooled systems can be made near silent while overclocking and still maintaining a modest form factor, with expandability even..
Quote:
The water just moves the problem around, so the engineering question is whether there's any advantage to doing that.
There are many advantages.
Quote:
Obviously, what works for a modestly spec'd notebook (for $3K?!) doesn't necessarily work for a high-end tower.
Why is that?
Quote:
Perhaps the Hitachi solution is better for that notebook, and perhaps it's just gimmicky (again, the iBook manages with smart passive cooling and a backup fan).
And perhaps it isn't. Considering that many people use it on desktops. Overclock with it. And it is still near silent.
Quote:
The cooling solution doesn't last as long as a good fan would, or an entirely passive cooling solution.
And how do you know this? And even if it did: So? Maybe a *good* water cooled system would last longer than a good fan.
Quote:
if Apple came up with a way to water cool these towers, people would bitch about the imminent price markup.
a tubular cooling sysytem isn't currently plausible in a tower becuase they are made for people to be inside and tinker with. And with people in there messing around, these systems are going to get damaged. Not to mention with all those tubes running all over the place it'd be as big a mess as the ribbons that were finally done away with.
It's easier to implement within a notebook because people aren't in there changing the configuration, and thus the level and areas of cooling will remain consistant. Whereas inside the tower as people expanded the effectiveness of the cooling zones may be compromised.
a tubular cooling sysytem isn't currently plausible in a tower becuase they are made for people to be inside and tinker with. And with people in there messing around, these systems are going to get damaged. Not to mention with all those tubes running all over the place it'd be as big a mess as the ribbons that were finally done away with.
why can't a water cooled system be made to allow modification?
Quote:
It's easier to implement within a notebook because people aren't in there changing the configuration, and thus the level and areas of cooling will remain consistant. Whereas inside the tower as people expanded the effectiveness of the cooling zones may be compromised.
Yeah, you might be right. Water cooling might never be used in a mass market desktop computer. Is that your guess?
why can't a water cooled system be made to allow modification?
Because let's face it, if Joe Blow tries to modify his cooling system and anything went wrong, you'll have liquid all over the internals of your computer, obviously laying waste to any warranty the owner may have possessed. And with customizable cooling configurations, the person making said customizations would need to things about thermal dynamics and other such areas of education that most people are not privied to. Just saying "this area is hotter so I'll run more pipe to it" is not an acceptable idea.
Quote:
Yeah, you might be right. Water cooling might never be used in a mass market desktop computer. Is that your guess?
Did I say that? Eventually, I'm certain this will happen. But I guarantee you no such technology will be available in a form that the average or even above average end consumer can arbitrarily reconfigure. This is very complex technology and not meant to be played with.
I'm trying to think of an example of expensive consumer products that are liquid cooled and allow the consumer to customize the cooling configuration. I'm not saying there aren't any, but I can't come up with one. Does anyone else know of any?
I'd also like to add that the hotter you make a machine run through upgrades, the faster you'll need to cool the liquid running through this machine. These systems are designed to cool the liquid down to a predetermined temperature in a predetermined amount of time. Once the machine becomes hotter, the liquid isn't cooled fast enough, and you have unstoppable heat buildup. Now you are asking the user to manually adjust the cooling rate and/or distribution of the coolant itself, and that's something virtually nobaody is qualified to do.
Because let's face it, if Joe Blow tries to modify his cooling system and anything went wrong, you'll have liquid all over the internals of your computer, obviously laying waste to any warranty the owner may have possessed. And with customizable cooling configurations, the person making said customizations would need to things about thermal dynamics and other such areas of education that most people are not privied to. Just saying "this area is hotter so I'll run more pipe to it" is not an acceptable idea.
What if it had an internal fan so if you did add something to it the fan could then be used in addition to the water cooling system? It wouldn't be silent anymore but it would still be less noisy than the alternative.
Quote:
Did I say that?
No, you didn't. That is why I asked.
Quote:
Eventually, I'm certain this will happen.
What will allow it to happen?
Quote:
But I guarantee you no such technology will be available in a form that the average or even above average end consumer can arbitrarily reconfigure. This is very complex technology and not meant to be played with.
- See my first answer in this post.
Quote:
I'm trying to think of an example of expensive consumer products that are liquid cooled and allow the consumer to customize the cooling configuration. I'm not saying there aren't any, but I can't come up with one. Does anyone else know of any?
Just because it hasn't happend yet doesn't mean it is impossible.
Also, the pee cees that are liquid cooled can be modified. You just have to follow the instructions to do it.
You could also pay your Apple dealer to do it like you have things done to your car. Considering that the ultimate G5 from the apple store costs more than some cars this doesn't seem entirely bizarre.
Quote:
I'd also like to add that the hotter you make a machine run through upgrades, the faster you'll need to cool the liquid running through this machine. These systems are designed to cool the liquid down to a predetermined temperature in a predetermined amount of time. Once the machine becomes hotter, the liquid isn't cooled fast enough, and you have unstoppable heat buildup. Now you are asking the user to manually adjust the cooling rate and/or distribution of the coolant itself, and that's something virtually nobaody is qualified to do.
You just need a thermostat and a radiator large enough to handle a higher capacity than the stock system. Autos have been doing this for a hundred years.
Comments
Then there is the issue of cost and reliability, both of which are affected by the complexity of liquid cooling systems. Fans are cheap and very reliable. Liquid cooling (for computers) costs more, and its reliability is far lower.
If Apple can achieve their design goals for noise and cooling capacity by using fans, there's little incentive to use a more complex and expensive solution.
Originally posted by Mac Force
-52 °C is -61.6 °F. There's not a single freezer that can achieve this. The next step in cooling, after such a compressor, is liquid N2.
Actually that's not true. I work in biomedical research, and we use freezers that achieve temperatures as low as -120? C. Dual compressors are used for -80? C, and quad compressors get down to around -120? C. -80? C freezers are very common, the other's less so because of cost and reliability. Liquid N2 is typically used for anything below -80? C in most labs.
I'd bet that with liquid N2 cooling, Apple could clock the G5 high enough to shut up the x86 whiners.
Originally posted by iSegway
Are you saying that watercooling isn't superior to air cooling with computers?
Well, duh.
Who wants to spring a leak? The major problem with air cooling is the noise, but 9 computer controlled fans with some amazing ventilation make this a non issue. Each of the 4 compartments within the tower can be independently cooled, meaning that the fans will be on as little as possible and turn as slowly as possible. Apple heard the complaints about the wind tunnel g4's, and I think they've addressed it.
Is it too much to ask to have a case that doesn't fill with dust?
I am going to laugh at all you nay sayers in a few years when water cooling becomes standard.
If I am wrong none of us will be laughing because our computers will will be as large as closets and be almost empty with a screen door type enclosure.
By the way... you are saying that it is more difficult/dangerous/expensive to put a water cooling system in a computer than it is to do this - link another link
Originally posted by Mac Force
-52 °C is -61.6 °F. There's not a single freezer that can achieve this. The next step in cooling, after such a compressor, is liquid N2.
Add dry ice to rubbing alcohol. Let the dry ice cool down the alcohol. As the dry ice sublimes it will make the rubbing alcohol look like sprite, but whatever you do, don't touch the alcohol- you will loose a part of your body. This is a decent intermediate step between a compressor and Liquid N2. Best of all, it doesn't place the same heat (cold) stresses on metal that LN2 can.
My previous comparison to nuclear energy isn't all that strange. The energy density of chips is thought to surpass the energy density of nuclear reactors unless Intel gets its act together with respect to heat. It is a shame that we can't convert infrared radiation directly into electrical energy (yet). Otherwise, you could get some power out of your CPU usage.
Water cooling only works in a closed system when you are using the water to move the heat from the hot thing to a radiator. Water doesn't give up its heat very easily, so you need a large radiator with lots of surface area. If you used a chemical other than water (with a lower specific heat), then you would need a smaller radiator. Some nuclear reactors use liquid sodium instead of water because once liquid, it very quickly absorbs heat. The reason why nuclear reactors do not have closed heat radiators is that there is no good way to dissipate 6000 Megawatts of heat through a radiator- You would need a radiator with many square miles of surface area. The soultion is to just evaporate the water and have an open system where you need more water. Sorry for the nuclear power lesson.
:-)
Originally posted by iSegway
By the way... you are saying that it is more difficult/dangerous/expensive to put a water cooling system in a computer than it is to do this - link another link
Actually, yes. Fuel cells are self-contained and isolated from the rest of the laptop. With water-cooled systems, you're placing the water container (pipes, tubes, whatever) directly against the electronics to be cooled, or at least exposed in the same section of the casing. And they can't be sealed tight (like a fuel cell) because that'll degrade their ability to absorb heat.
Apples and Oranges.
Originally posted by Kesh
With water-cooled systems, you're placing the water container (pipes, tubes, whatever) directly against the electronics to be cooled, or at least exposed in the same section of the casing.
Apples and Oranges.
Isolated, hunh. Interesting. Yea, my design involved just running the water over the unprotected circuitboard.
Funny how fuel systems can be *totally* isolated but not water. Strange.
Apples and oranges... yeah... ok. lol
So let me get this straight. You are telling me that in your opinion there will never be a mass production water cooled personal computer(desktop that is, since there have already been laptops that incorperate water cooling.)?
If there will be be a mass production water cooled computer someday what kind of technological advancement will be necessary?
[quote]NEWS
Hitachi has begun to sell its new water-cooled notebook computer in Japan. The Flora 270W Silent Mode, as it is called, sports a 1.8GHz mobile Pentium 4, 128 MB RAM, 20 GBhHard drive, and a 15-inch TFT screen. The cost of the machine is a mere 341,000 yen (US$2,941).
Interestingly, the notebook uses a patented Hitachi water-cooling system. Flexible tubing is placed over the chips in the machine and water is pumped through them, taking the heat with it. The tubes then run the water into a tank on the back of the TFT screen that is visible and meant to be aesthetically pleasing. Hitachi says that the tank has been made visible just to differentiate the notebooks from other machines, and that it could easily be hidden.
In terms of cooling performance it is on equal terms with air-cooling, but it has the added advantage of being a much quieter solution. Reliability-wise, the solution lasts more than 5 years, the tubing can circulate the solution 20,000 times, and the pump works for more than 44,000 hours. Hitachi offers a three-year guarantee with the machine.
Hitachi started taking orders on Wednesday and can supply to corporate users outside of Japan, although it is undecided into which consumer markets the notebook will be released. Hitachi is also in talks with companies who want to use the system in servers and plasma display devices. As well, Hitachi is pushing for the cooling technology to become an industry standard.[quote]
The issue is not as simple as "water cooling is better" or "water cooling is worse." You have to look at the problem, and part of the problem, as Fawkes pointed out, is that water cooling is air cooling. The water just moves the problem around, so the engineering question is whether there's any advantage to doing that. Obviously, what works for a modestly spec'd notebook (for $3K?!) doesn't necessarily work for a high-end tower. Perhaps the Hitachi solution is better for that notebook, and perhaps it's just gimmicky (again, the iBook manages with smart passive cooling and a backup fan). The cooling solution doesn't last as long as a good fan would, or an entirely passive cooling solution.
As an aside, the mention of liquid sodium as a coolant reminded me of when the Superphenix breeder reactor in France had a coolant leak, not quite 20 years ago. It used (and probably still uses) liquid sodium, so the leak turned one room in the plant into a giant, perpetual fireball. Since the reactor's a breeder (self-fueling) it couldn't be shut down quickly or easily, and since the leak was behind a big fireball they couldn't plug it easily. Now there is an engineering challenge! (The last I heard they were pumping sodium in as fast as it was leaking out, but I can't imagine that was the permanent solution.)
The difference would be that with air cooling, Apple can use lots of fans running slowly to cool the components; with water cooling they'd have to have a couple of fans frantically cooling a specific part (the radiator), which would make them louder.
No you wouldn't. This is absolutely wrong.
The issue is not as simple as "water cooling is better" or "water cooling is worse." You have to look at the problem, and part of the problem, as Fawkes pointed out, is that water cooling is air cooling.
No! Water cooling is not air cooling. Air cooling is air cooling. Water cooled systems can be made near silent while overclocking and still maintaining a modest form factor, with expandability even..
The water just moves the problem around, so the engineering question is whether there's any advantage to doing that.
There are many advantages.
Obviously, what works for a modestly spec'd notebook (for $3K?!) doesn't necessarily work for a high-end tower.
Why is that?
Perhaps the Hitachi solution is better for that notebook, and perhaps it's just gimmicky (again, the iBook manages with smart passive cooling and a backup fan).
And perhaps it isn't. Considering that many people use it on desktops. Overclock with it. And it is still near silent.
The cooling solution doesn't last as long as a good fan would, or an entirely passive cooling solution.
And how do you know this? And even if it did: So? Maybe a *good* water cooled system would last longer than a good fan.
if Apple came up with a way to water cool these towers, people would bitch about the imminent price markup.
How much would the price mark-up be?
It's easier to implement within a notebook because people aren't in there changing the configuration, and thus the level and areas of cooling will remain consistant. Whereas inside the tower as people expanded the effectiveness of the cooling zones may be compromised.
Originally posted by rageous
a tubular cooling sysytem isn't currently plausible in a tower becuase they are made for people to be inside and tinker with. And with people in there messing around, these systems are going to get damaged. Not to mention with all those tubes running all over the place it'd be as big a mess as the ribbons that were finally done away with.
why can't a water cooled system be made to allow modification?
It's easier to implement within a notebook because people aren't in there changing the configuration, and thus the level and areas of cooling will remain consistant. Whereas inside the tower as people expanded the effectiveness of the cooling zones may be compromised.
Yeah, you might be right. Water cooling might never be used in a mass market desktop computer. Is that your guess?
Originally posted by iSegway
why can't a water cooled system be made to allow modification?
Because let's face it, if Joe Blow tries to modify his cooling system and anything went wrong, you'll have liquid all over the internals of your computer, obviously laying waste to any warranty the owner may have possessed. And with customizable cooling configurations, the person making said customizations would need to things about thermal dynamics and other such areas of education that most people are not privied to. Just saying "this area is hotter so I'll run more pipe to it" is not an acceptable idea.
Yeah, you might be right. Water cooling might never be used in a mass market desktop computer. Is that your guess?
Did I say that? Eventually, I'm certain this will happen. But I guarantee you no such technology will be available in a form that the average or even above average end consumer can arbitrarily reconfigure. This is very complex technology and not meant to be played with.
I'm trying to think of an example of expensive consumer products that are liquid cooled and allow the consumer to customize the cooling configuration. I'm not saying there aren't any, but I can't come up with one. Does anyone else know of any?
Because let's face it, if Joe Blow tries to modify his cooling system and anything went wrong, you'll have liquid all over the internals of your computer, obviously laying waste to any warranty the owner may have possessed. And with customizable cooling configurations, the person making said customizations would need to things about thermal dynamics and other such areas of education that most people are not privied to. Just saying "this area is hotter so I'll run more pipe to it" is not an acceptable idea.
What if it had an internal fan so if you did add something to it the fan could then be used in addition to the water cooling system? It wouldn't be silent anymore but it would still be less noisy than the alternative.
Did I say that?
No, you didn't. That is why I asked.
Eventually, I'm certain this will happen.
What will allow it to happen?
But I guarantee you no such technology will be available in a form that the average or even above average end consumer can arbitrarily reconfigure. This is very complex technology and not meant to be played with.
- See my first answer in this post.
I'm trying to think of an example of expensive consumer products that are liquid cooled and allow the consumer to customize the cooling configuration. I'm not saying there aren't any, but I can't come up with one. Does anyone else know of any?
Just because it hasn't happend yet doesn't mean it is impossible.
Also, the pee cees that are liquid cooled can be modified. You just have to follow the instructions to do it.
You could also pay your Apple dealer to do it like you have things done to your car. Considering that the ultimate G5 from the apple store costs more than some cars this doesn't seem entirely bizarre.
I'd also like to add that the hotter you make a machine run through upgrades, the faster you'll need to cool the liquid running through this machine. These systems are designed to cool the liquid down to a predetermined temperature in a predetermined amount of time. Once the machine becomes hotter, the liquid isn't cooled fast enough, and you have unstoppable heat buildup. Now you are asking the user to manually adjust the cooling rate and/or distribution of the coolant itself, and that's something virtually nobaody is qualified to do.
You just need a thermostat and a radiator large enough to handle a higher capacity than the stock system. Autos have been doing this for a hundred years.