Interesting new CPU cooling device

[Groltz]

Active Cool has developed the AC4G, the world's first power solid-state cooling system for PC processors. AC4G is an entirely new approach to cooling PC processors that is poised to replace the standard heat sink and fan technology in PCs with fast processors.

http://www.activecool.com/products/ac4g.html

 

[NRG = mc²]

How does this work? Looks like a PCI card?? :-?

 

[The JoJo]

Have you seen the swiftech review over at overclockers.com ? It has a peltier integrated into it. Seems to work pretty well.

Worth to check it out!

 

[Jake the Dog]

i'm very interested in reading a review of this particular ActiveCool product. please, if anyone comes across one, post the link here.

thanks.

 

[blakerwry]

It has a peltier integrated into it.

just to bash a little... i like how the illustration aprears to show a fan... now that's new solid state technology for you....

also I have to say that peteirs are nothing new... I remember buying them for socket 7 cpu's... They were even available at the local tech shops...

Peltiers seemed to drop out of style because thermal management solutions were not widely available or reliable and you had no other way of determining if your pelteir went out... atleast now we have good motherboard level monitoring that will shut off hot CPU's... and every motherboard that I have seen in the last year or two has had some way to track CPU temps from within an OS.

On the noise side of the issue, peltiers created just as much heat(if not more) than they reduced(one side got hot while the other side got cooler). You still needed a fan and heatsink to dissapate the heat.... That's where water cooling came in... it allowed for larger area to disapate the heat.. could be quiet.... was considered more reliable... and was a neat project to impress your friends... it's only downside was it's expense and installation difficulty.

 

[Stereodude]

It has a peltier integrated into it.

just to bash a little... i like how the illustration aprears to show a fan... now that's new solid state technology for you....

Now it's my turn to bash a little. If you've been paying any attention to modern cooling solutions you'd know there's no way that fan is cooling a peltier. We have CPUs that are approaching thermal loads of 90W. Even with a large copper Heatsink you still need a large 60mm fan or an 80mm fan to keep the thing reasonable cool. That fan is hardly adequate to cool a video card, let alone a 90W thermal loaded chip. There's obviously a lot more to it.

There is also no reference to a peltier on the Active Cool page. If I recall correctly it converts heat into electricity and then back to heat where it's expelled from the rear of the PC (via the PCI slot thiny). I'm not 100% sure about that, but I am 100% sure that they're not just selling a Peltier.

Stereodude

 

[Cliptin]

There is also no reference to a peltier on the Active Cool page. If I recall correctly it converts heat into electricity and then back to heat where it's expelled from the rear of the PC (via the PCI slot thiny). I'm not 100% sure about that, but I am 100% sure that they're not just selling a Peltier.

Stereodude

I spotted some research a few months ago where some scientists in Iceland(?) had developed a way to convert heat into electricity by the use of superconductors (I think). The expense was greater per MW than wind power.

 

[blakerwry]

While traditional cooling methods run fans continuously, causing increased noise as fan speeds increase to maintain stable temperatures, AC4G dynamically reduces PC fan noise by pumping heat out of the processor using a noiseless electronic heat pump.

Geared towards the global PC OEM and white box manufacturing markets, Active Cool's innovative AC4G solution addresses both the heat and noise problems.

Active Cool's new AC4G product has the following features:

-- Microprocessor-controlled thermo-electric cooling

-- Significantly reduced PC fan noise

-- Cools Intel Pentium 4 up to 4GHz; cools new AMD K8 processors

-- Maintains CPU temperatures at 26(degree)C during normal operation

-- Powered independently of the PC

-- Installs in any PC in less than 90 seconds

 

[Stereodude]

Your point Blake? (assuming you have one)

Clearly it's not a peltier. Again, if you have a high end P4 CPU pumping out 80W of heat under a full thermal load. You would need a peltier capable of about 1.5x that 80W in order to hold a 26C temp. That means you need 120W pelier and a way to power it. That also means you have 200W of thermal energy to dissipate. If you think that the small heatsink that's on that thing can dissipate 200W of thermal energy with that tiny fan you're a fool.

Lets look at what they say:
- Innovative
- quiet (less fan noise)
- noiseless electronic heat pump
- thermo-electric cooling

Now, which of those apply to a peltier? mayble the last two if you're very generous.

Looking at the picture and from the PR on their site I feel very confident when I say it's not a peltier.

Stereodude

 

[Tea]

Time to apply a little logic and evidence here guys.

Thus far, the thread seems to have generated a great deal of heat and very little light. Let's think about it, shall we?

While the Active Cool website is conspicuously lacking in hard information, we can glean several pertinent facts from it.

• 1: The entire site makes absolutely no mention of peltiers, yet it does mention the other known cooling methods. From this we can deduce the following possibilities:
  • They have invented something entirely new to science which is completely unrelated to existing peltier technology, and for some incomprehensible reason they not only fail to mention this in their press release, they also think that selling it in penny packets to companies like ThermalTake (who operate inside of what is in global terms a tiny nice market) is a good way to commercially exploit this ground-breaking scientific invention.
  • They have never heard of peltiers or consider them not worth mentioning, even though they do mention conventional refrigeration methods, fans, and so on.
  • The device is, in fact, a combination of a peltier and a standard HSF. Extra evidence for this scenario is provided by the care with which they do not mention peltiers - for their fear is that if consumers and OEMs learn that the device is simply a combination peltier and conventional HSF, they will either ignore it (seeing it is nothing new) or simply design and manufacture their own home-grown clone of it. After all, how hard could that be?
• The Active Cool web site is full of meaningless PR buzz words like "innovative" and devoid of any actual substantive content. The three external links they provide lead directly to regurgitations of their press release and provide no additional information about what the device is, or how it works.
  
• The pictured HSF looks to be about the same size as a typical small to middling stock commercial cooling system for OEM use (such as, for example, the HSF that AMD ship with their boxed Athlon XP processors). From this, and from the fine pitch of the cooling fins, we can reasonably expect that, shorn of its unique "electronic heat pump" attributes and operating as a normal HSF, it is capable of cooling low-end to mid-range processors. By the look of it, it would do for a Duron and maybe an XP 1600 but might struggle with a 2200. Given this baseline cooling ability, the peltier component (or whatever else it is that they are using) does not need to dispose of the entire ~60W generated by the CPU, but only of the difference betwen total CPU load and the capacity of the conventional air-cooled HSF - let's say about 20W for current higher-end processors, and double this to allow some room for growth.
  
• Taking Sterodude's 1.5x dissipated heat figure, and assuming that the mystery device is indeed a glorified peltier, we multiply it out and discover that it has an estimated minimum max power consumption of 1.5 * 40 = 60W, and (in my estimation) a probable max power consumption of rather higher than that, perhaps 100W.
  
• From this, we can deduce that, if the above is correct, then the power drain of the cooler is such that powering it off a standard computer PSU is impractical, and that a seperate, external power supply is required. And - hey presto! - that is just what ActiveCool are doing.
  [/list:c599f62cdd]
  Conclusion: if it is just a glorified peltier, then the Active Cool website is exactly what we would expect to see - long on buzz-words, very, very short on detail. If it ain't a glorified peltier, then we must explain why, seeing as these guys have come up with something that looks just like a peltier but is greatly superior to one, they have made no effort whatsoever to show that their product is different and better.

 

[Stereodude]

Tea,

You're failing to take into account that it says it can cool a 4Ghz P4. A P4 at 4Ghz has a thermal load in excess of 100W. You have to cool the thermal load of the CPU and that of the peltier, not just the difference. There's no way that thing can cool dissipate a 200W thermal load in a poorly ventilated (quiet) case.

Again as I keep harping on with Blake you simply can't aircool the hotside of a peltier unless your case is extremely well ventilated. Even then you need a heatsink and fan combo more in line with the top of the line Swiftech units with a 70+ dB fan. The HS and Fan is simply too small (even without the "active" element) to cool anything above a 1600+ let alone a K8 or a 4Ghz P4. An active element only makes matters worse.

Also, from their PR, "Early customers of Active Cool’s AC4G product include Thermal Take, GlobalWin, Titan and ADDA, all of whom have successfully tested the product." If the product was just BS and a rehashing of old technology why are the known names in the HSF world paying for the technology?

Here's something else to throw in the mix. http://www.proside.co.jp/o_parts/blueice/index.html Is this just a glorified Peltier too?

Stereodude

 

[jtr1962]

If they are using a conventional Peltier, then it is correct that you would need a 120W or so device to cool an 80W processor. To keep it at 26° C you would need to keep the hot side of the Peltier at around 50° C. The Peltier would be drawing about 110 to 120 watts(the wattage rating of a Peltier is the maximum heat that it can pump at zero temperature differential, not the power that it uses). This would give a total heat load approaching 200 watts. Assume that the environment in the PC case is 40°C maximum. This means the heat sink must dissipate 200 watts with a temperature rise of 10°C, which is a thermal resistance of 0.05°C/W. Clearly the little heat sink/fan in the picture is not up to this task. You would need one of the following:

1)a liquid heat sink

2)a bonded fin heat sink about 5"x5"x4" high plus a 120 mm fan

3)an 8" x 12"x2" high extrusion plus a 160mm fan

The small heat sink in the picture will at best offer a thermal resistance of around 0.25°C/W.

Therefore, we are definitely not dealing with a conventional Peltier. Since the device is "electronic", it is not a compressor, either.

It is possible that they have a much more efficient Peltier(current devices operate at less than 10% of the maximum possible efficiency, termed the Carnot efficiency). At the Carnot efficiency, you only need 6.5 watts to keep an 80 watt microprocessor at 26°C(assuming the heat sink is at 50°C). Let's say a device exists that operates at half the Carnot efficiency. You then have only 93 watts total that you need to get rid of, and suddenly that small heat sinkmight be up to the task if you can keep the air in the case under 30°C. That's certainly an easier job when you have less total heat to get rid of.

If they have indeed invented a much more efficient Peltier(or similar cooling device), then they are the world's biggest fools choosing this as it's first application. At best, CPU cooling is a niche application for Peltiers. The real money would be in conventional refrigeration, and a device this efficient(and noiseless to boot) would obsolete compressor-based refrigeration in short order. It could literally make someone a trillionaire since it can also also be used to efficiently generate electricity from low-level heat sources like geothermal heat, thus making fossil fuels and nuclear fission obsolete. In short, it could change our world for the better very quickly, and I'm sure anyone smart enough to invent an improved Peltier would be smart enough to see it's potential. Therefore, I highly doubt that it's an improved Peltier. Either that, or my opinion of marketing departments just went even lower than even I thought possible(all those idiotic auto commercials are mainly responsible for my low opinion of marketing "professionals").

What is it? I haven't a clue, but if it's hyped as much as the Segway, we're in for a big disappointment.

 

[The JoJo]

Hmmm, if this peltier-activecool thing is based on my post, I apologize. My post was in no way related to the first post, I just wanted to point people to another new(for me atleast) cooler:

http://www.overclockers.com/articles646/

 

[Tea]

I remain unconvinced, Stereodude.

I don't know anything about peltiers, or fancy cooling of any kind for that matter - Sol and Groltz seem to be the resident experts here in that department, alongside NRG and perhaps your good self - but I'm Tannin-trained and I can spot shonk blindfold at a thousand paces.

And regardless of the supposed merits of the device itself, that marketing crap on their web page is quite clearly shonk. I ask myself the following questions:

1. If they honestly have made a breakthrough, why don't they say so?
   
2. If the device is not just a glorified peltier, why don't they explain that too? Indeed, why does the dreaded "P" word not rate a single mention on their entire site?
   
3. What possible purpose can the PCI interface serve?
   
4. Why are they so coy about the mains power?
   
5. If ThermalTake are so good at spotting great ideas and not taking up the complete duds, how do we explain their incredibly useless Orb range of products?

I agree with you that some mystery remains, but as JTR points out, a real breakthrough would be most unlikely to appear as a computer accessory.

What's inside that large PCI card?

 

[Groltz]

I don't know anything about peltiers, or fancy cooling of any kind for that matter - Sol and Groltz seem to be the resident experts here in that department

All my focus has been on air cooling. I have never used peltier or water cooling on a PC and am only familiar with the rudiments of their use.

If they honestly have made a breakthrough, why don't they say so?

The product has not even been launched yet. According to the Active Cool website, the "AC4G (is to) to be launched at COMDEX, Las Vegas, November 18–22, 2002"

[*] What possible purpose can the PCI interface serve?

(Quote)The AC4G system uses several different sensors on its device, which is similar in size to conventional heat sink/fan configurations but adds the thermoelectric pump to one component and a separate controller that plugs into a computer's PCI (peripheral component interconnect) slot. (End Quote)

[*] Why are they so coy about the mains power?

Mains power? (Quote)"But the Test Center did have two complaints. First, because it is powered independently of the PC, the cooling system requires an extra outlet..."(End Quote) It appears that this unit uses separate AC power to run.

[*] If ThermalTake are so good at spotting great ideas and not taking up the complete duds, how do we explain their incredibly useless Orb range of products?

A learning curve by the looks of it. While admittedly TT's orb-based CPU-coolers are turds, their orb-based VGA coolers work quite well. (Blue Orb. Crystal Orb) Hercules, in fact, used the TT Blue Orb on their original GeForce 3 card. TT now sells the better-designed and effective Volcano series coolers for CPUs.

I agree with you that some mystery remains, but as JTR points out, a real breakthrough would be most unlikely to appear as a computer accessory.

Might as well find breakthroughs in a part of the market that isn't so saturated with the same. It has been seen that people are pouring a lot of money into aftermarket cooling products. A company with an innovative product could possibly make a good profit in this arena depending on the quality, price, and usefulness of their invention.

What's inside that large PCI card?

The cooling system's controller, apparently.


http://www.activecool.com/newsandevents/AC4GLaunch.pdf

http://staging.infoworld.com/articl...l.xml?Template=/storypages/printfriendly.html

http://crn.channelsupersearch.com/news/crn/38154.asp

 

[blakerwry]

stereodude, why do you keep "Harping" on me..

i never said that they were using a pelteir... I simply said that (1) a pelteir is not new or innovative in any measure of the word (2) that peltiers generate more heat and thus more noise that they're worth... which would make it seem likely that this isn't just a pelteir unit...

 

[jtr1962]

Another remote possibility is that the device is using a heat pipe. A heat pipe is a vapor filled tube which has very high thermal conductivity. By using one you can remove heat from a cramped space where a large heatsink/fan won't fit, and move it somewhere else where you get rid of it. You ultimately still need to get rid of the heat somehow, however. You can't just "turn it into electricity" as some here have suggested. You can turn heat flux into electricity by applying a thermal gradient across a thermoelectric device(it takes energy to do this). However, this is an inefficient way to make electricity since the current efficiency of themoelectrics is abysmal. It is used where no other method exists, such as by using nuclear isotopes to make heat in order to make electricity and power spacecraft. All deep space probes are powered this way because they go too far from the sun to use solar cells.

 

[Stereodude]

stereodude, why do you keep "Harping" on me..

i never said that they were using a pelteir... I simply said that (1) a pelteir is not new or innovative in any measure of the word (2) that peltiers generate more heat and thus more noise that they're worth... which would make it seem likely that this isn't just a pelteir unit...

That would explain why you went on a "Peltiers are nothing new" bash a few posts up. Because you didn't think it was a peltier. This makes so much more sense to me now. Thanks for clearing it up.

Stereodude

 

[blakerwry]

You can't just "turn it into electricity" as some here have suggested.
...
However, this is an inefficient way to make electricity since the current efficiency of themoelectrics is abysmal.

Even if it is a bad way to make electricity, is it still a good way to get rid of heat?

Is it feasable for it to be used in a PC?

 

[jtr1962]

You can't just "turn it into electricity" as some here have suggested.
...
However, this is an inefficient way to make electricity since the current efficiency of themoelectrics is abysmal.

Even if it is a bad way to make electricity, is it still a good way to get rid of heat?

Is it feasable for it to be used in a PC?

It's not a good way to get rid of heat, either. The thermal conductivity of Peltier modules, even when short-circuited, is rather poor(as it must to achieve even their rather poor efficiency as refrigerators), so this increases the thermal gradient necessary to get rid of a given amount of heat, which basically means much higher hot side temperatures than just a conventional heat sink. In fact, the figure of merit Z of Peltiers, which is a way of measuring their efficiency as either generators or refrigerators, is inversely proportional to their thermal conductivity and electrical resistance, and directly proportional to their Seeback coefficient(a measure of the thermoelectric effect).

 

[Jake the Dog]

thermaltake have released a similar product. looks lik ethe the PCI device is nothing more than a glorified fan controller and power bus. still, it should work well.

http://www.thermaltake.com/products/subzero/subzero4g.htm#k7

 

[honold]

just joining the thread...better late than pregnant, right?

quoth http://www.cluboverclocker.com/comdex/thermaltake.htm :

"Another new toy Tt was showing off was the SubZero4G. The SubZero4G uses a pair of TEC (Peltier) coolers sandwiched between a heavy duty aluminum CPU cooler and a aluminum cold plate. Sound familiar? Yes, it's the exactly the same type of cooling we use to experiment with years ago so this technology is as old as overclocking itself. The only real new thing the SubZero4G has to offer is a standalone power supply. TEC are fun to play with, but they introduce massive amounts of heat to the interior of your case as well as condensation that can cause your system to short out. However, as long as the user knows the benifits, as well as the risks, the SubZero4G should be a big hit."

 

[honold]

more http://www.anandtech.com/newsletter/readarticle.html?i=30&nl=y here

 

[jtr1962]

The idea of having a controller is a good one-if it's done properly. I've seen too many temperature control devices that control cooling by having the cooling element(usually a compressor) full on all the time and using a heating element to counteract the cooling effect and stabilize at the desired temperature. The usual excuse given for such an abhorently inefficient(and stupid I might add) setup is that it's not possible to control the speed of the compressor. This is complete nonsense nowadays with the state of power electronics. It may cost more to manufacture such a system, but the payback time is very short due to the power saved(and wear and tear on the compressor). Also, a throttled down compressor is obviously quieter. I wish room air conditioners worked this way instead of cycling the compressor on and on.

With Peltiers(which are simlar to a resistive load), the control circuitry is nearly trivial. Hopefully they're using a switching, rather than linear, power supply for greater efficiency. And I certainly hope they're not using the control board for a heating element to counteract the cooling effect of a Peltier which is left full on all the time, or just cycling the Peltier on and off(this type of pulsing is damaging to these devices over the long term).

I'm surprised this wasn't done sooner. Peltiers aren't particularly efficient, and their efficiency drops dramatically as the input current approaches Imax. Coincidentially, the usually occurs with an input voltage of 12 volts for a typical 127-element cooler, so it is obvious that until now the Peltiers were run in the most inefficient portion of the power curve. If you drop the current to, say, 80% of Imax, your input power drops by something like 40% and your cooling effect only by 5%. Hopefully if these people did their homework this is what they're doing. Preventing condensation also prevents damage to the Peltier. In fact, condensation due to poor sealing is the number one way that these devices fail in service.