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SubZero Chilled Alcohol PC Cooling
Joseph Tan writes:"Tech-Junkie's own attempt on a liquid cooling project, this time we used a combination of liquid alcohol and frozen carbon dioxide. Less than -65 degrees Celsius was achieved, and amazingly our motherboard and CPU are still alive.
"
What happens if somehow it malfunctions and you get deadly carbon dioxide released into your room.
Carbon dioxide is not toxic.
The only possible dangerous scenario would be filling the entire room with CO2, in which case you'd suffocate (no oxygen). However, with any ventilation at _all_ this can't happen.
Caveat: Don't fill a basement with CO2. It's heavier than air, and will just sit there. If you start feeling drowsy after a minute or so, get out.
Lastly, they had a total of 4 kg of CO2. Gaseous CO2 at room temperature has a density of about 1.7 kg per cubic metre. Even if *all* of the CO2 vapourized *and* they were in a basement and had no ventilation, the suffocating pool of CO2 would come up to about their ankles.
In summary - No danger.
For everyone reading this thread still (and I know you're out there, you keep replying): This was a mistake. I was thinking of carbon monoxide, not C02. It has been pointed out that I was wrong. Stop replying to me. It wasn't a troll, it was a brain fart. I know that C02 is relatively harmless, unless you touch it (dry ice will freeze the skin cells).
kwsNI
Thanks. I knew that. Just a temporary brain fart (one of the possible, non-leathal side effects of too much CO2). Anyways, as you and every other /. reader except for John Carmack has pointed out, I've gotten my gasses mixed up and there is no real danger to CO2.
kwsNI
I like to buy it from Basket-Robbins ice cream parlors - they sell it by the pound. They stock up just before Halloween, since it's apparently quite popular for putting into punch bowls at Halloween parties.
I like to buy a pound on the way back from lunch, crack it into small pieces with a rock, then drop the little chunks in my coworkers' coffee when they're not looking. I was surprised by how many people didn't realize what I had done to their coffee - I thought EVERY ex-high school/college student had played with dry ice at some point.
It's not for the performance the oc'ers do it, it's the chanlenge of 'what if'
In the case of one guy who was using liquid oxegen or nitrogen? and florinert and the transfer liquid. it would have been cheaper to BUY the board/memory etc for cost of doing the Overclocking. eg. $1000 for the florinert, $X for the LOX, $Y for the misc hardware and construction.
make Linux, not Microsoft. sin(beast) = -0.809016994374947424102293417182819
Thanks, someone already explained that to me. My mistake. Good thing I'm a geek and not a chemist...
kwsNI
I think its on disc 2, Lain's uber-computer has a greenish-bubbly-liquid that she uses for coolant. Yet another example of anime showing future technology.. er.. okay, so at least 1 example ^^;
no
I really wish these massive overclockers would boot linux every once in a while. I say that because as they say in this one "At 616 it wouldn't boot Windows." Well...how far did it get? Maybe the IDE controller stops responding... if they'd boot linux then they'd at least have a better chance at seeing WHAT was failing...
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Um, if that was the whole point of this experiment....wasn't it a bit redundant? I mean, people have chilled their systems beyond this point, many with better results. What was the point?
Anyway, the technique they used wasn't a very good one. The best way to cool a system is DIRECT CONTACT. They placed the motherboard in a bag, and submerged the bag in the chilled alcohol. No doubt, the cool air surrounding the bag lowered the temperature of the board (obvious by the overclocking results), but this is definitely inferior to less elaborate set-ups where cooling is *directly* applied to the system's components.
The results of this experiment weren't all that impressive.
This group was also risking the actual computer system BIG time. The fact they had to [try to] seal the board from the liquid makes this a risky undertaking. I'd feel more comfortable giving my board a bath in something a bit less conductive, like Mineral Oil.
Plus, they like to destroy working laptops. Okay, I can see the 286's being whacked, but those 386's could be used for SOMETHING other than target practice, no?
-- Give him Head? Be a Beacon?
-- Give him Head? Be a Beacon? :P)
(If you can't figure out how to E-Mail me, Don't.
Obviously you didn't read the article at all, or this would be painfully obvious, even if you didn't know it beforehand. Frozen CO2 is dry ice, and is commonly available. It is not dangerous when handled properly, and has many common application, such as chemistry experiments, and making ice cream.
Here is what I expect to see next...
Today Mr. Random Geek launched his motherboard and CPU into deep space hoping to achieve another 4 FP operations per hour. Mr. R.G. said "Liquid oxegen just wasn't cuting it anymore. I had To do something.. buying new hardware just isn't an option for me, I'll be overclocking this 486 for the REST of my life!"
YouTube & Google Video -> podcast http://castcluster.blogspot.com/
I wonder what are the limiting factors to the range of temperatures that the components of a PC can support (both high and low). Since they are not subjected to mechanical stress, the metal parts should handle low temperatures well enough, and, IIRC, silicon is rather stable thermally.
However, I am amazed that my own PIII is still alive at +75C, without overclocking. And let's not talk about the stability of Windows in such conditions. BTW, if anyone knows a solution which is less expensive than changing it (or than using dry ice ), I'd be glad to hear it.
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No, CO2 is hazardous on its own. If you don't know WTF you're talking about, then shut the Fortran up.
Mammals breathe oxygen in and CO2 out. Most of our breathing processes are regulated by the amount of CO2 in the nearby atmosphere, and if you increase that even slightly, all sorts of bad shit start to happen.
If CO2 is so nice to breathe, then there's a hundred dead Russian sailors who'd like to explain something to you.
"A little for the computer, a little for me! A little for the computer, a little for me!"
Ah, Simpsons.
--Lenny
What, me worry?
Actually, the human body is sensitive to the concentration of CO2 in the air. When it goes up, the presence of CO2 in the blood triggers a suffocating feeling (e.g. hold your breath).
However, inert gases (N,He...) do not trigger this feeling, but neither contribute to the oxygenation of your body. Since you are still breathing, you keep your blood's CO2 level low and feel fine. (Until you suffer from the lack of oxygen, which is what you are trying to avoid.)
Conclusion: Get in a room full of CO2, you'll know quickly you should get out.
Get in a room full of inert gases (or toxic ones), tougher luck.
CO2 is toxic in concentrations of a few percent. Remember, not only do you have to get oxygen into your blood, you also have to get the CO2 out. You body cannot tolerate the blood concentration of CO2 that will result from a 10% atmospheric concentration.
Ryan
> Carbon dioxide is not toxic unless you are exposed to insanely high levels.
This isn't true. You just pulled that "fact" out of your ass. Concentrations of CO2 (that's dioxide, the stuff your exhale) around 10% will make you feel funny; 30% will quickly kill. CO2 concentration in the atmosphere is about 0.035% by volume. About 350 parts per million.
Ryan
it'd be possibly dangerous to immerse the motherboard directly in the methanol due to localized heat spots that could cause boiling), and besides, the methanol would probably dissolve the plastic components.
I thought you could only do about -20 with a methanol refrig. loop.
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It's true that sometimes people faint before they can get out of this sort of situation. It happens a lot with workers in steel tanks, where rust has removed all oxygen from the atmosphere.
Bruce
Bruce Perens.
Bruce
Bruce Perens.
kwsNI dun said:
Actually, frozen Carbon Dioxide (as you so quaintly put it) is fairly readily available and mostly requires thick gloves to handle. It's otherwise known as "dry ice". ;)
My father, who used to work for the water company here in town, could get it fairly easily; that plus water plus some flashing strobe lights added up to spooky cauldrons on Halloween for the kiddies. :)
You can prolly get it at packing companies and the like. It's also what is commonly used to keep stuff like hearts for transplant (and biological samples) cold till they get where they need to be; the stuff is common enough that researchers in remote parts of Africa can get it to freeze samples of stuff like blood samples of Ebola patients.
Nothing, unless you've got a ton of carbon dioxide, in which case you MIGHT suffocate...but you'd have to have an awful lot of dry ice to ever get enough to suffocate yourself. (I think maybe you're confusing carbon dioxide (which is just good old dry ice, might give a freeze-burn but nothing serious) with carbon monoxide (which is a deadly killer since it replaces oxygen in your blood)...carbon dioxide is not poisonous, even the amount of dry ice to make a big cooler put out a lot of "smoke" isn't deadly (in fact, that's largely what they use for "smoke" effects in movies--dry ice in water! :) and your plants would love you (since they breathe carbon dioxide and exhale oxygen). :)
No hazmat suit needed. Mostly some good, thick gloves if you're going to be handling amounts sufficient to cool a motherboard (seriously--that much is not enough to suffocate or cause any more harm than a nasty case of frostbite if you handle the stuff with bare hands). You may want to make sure you're in a well-ventilated room just to be safe, but that's pretty much true with any stuff that cold, not to mention computer equipment.
(Chairman Kaga mode on) If memory serves me right (Chairman Kaga mode off) one of the competitors on "Iron Chefs" even used dry ice to freeze immature salmon to make sashimi. If the stuff is safe enough to pack hearts for transplant in and to freeze fish, it's safe enough to use on your computer. I've even used it before (along with glow-sticks in Ziploc baggies and a goodly amount of liquor and Mountain Dew :) to make a well drink called "swamp gas" in a cooler for Halloween parties (the carbon dioxide makes "smoke" effects from the water as well as bubbles--it's directly sublimating--and it freezes the alcohol into slush).
Literally the only thing I've ever seen that classified dry ice as hazmat was in shipping papers for truckers, and they literally classify almost everything as hazmat (including paint, empty barrels, tires, etc.). :) Don't worry. Putting dry ice on your motherboard is not going to kill you unless you're in a very enclosed space (if that's the case, don't eat chili, as your own farts might well kill you in just such a case much as it did one infamous Darwin Award nominee :). You will probably see a lot of neat smoke-like stuff coming from the computer (no, it's not broken--that's just the dry ice sublimating and freezing the water particles in the air). Put plants nearby and they'll make lots of oxygen and probably grow really well. No harm done, save maybe to the motherboard and your budget. :)
-Windigo The Feral (NYAR!)
I don't have any modern statistics on this at all (surely someone does) but I remember that the Pentium 50 systems that ran with the bus at 50 were slightly faster than the Pentium 66 systems with the bus at 33.
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Actually, as the carbon dioxide boils off from dry ice, it does give somewhat of a 'taste' to the air, slightly acidic. This is from the cold carbon dioxide dissolving in water, in the air or in your lungs, changing the PH.
I do not deploy Linux. Ever.
Some anonymous coward dun said:
Well, yes, if you're bloody stupid enough to go huffing it. For that matter, paint thinner and White-Out can also kill you by huffing them, and they take considerably less amounts to do so. For that matter, breathing water will kill you like that, because lungs aren't quite as efficient at gas exchange in water as gills are.
Warning: slight technical discussion ahead. Please skip if not interested in mechanics of suffocation. ;)
Actually, carbon monoxide takes a hell of a lot less to kill you than carbon dioxide does, and it kills largely by a somewhat different mechanism. Specifically, carbon monoxide actually binds more tightly to hemoglobin than oxygen does, forming methemoglobin (which accounts for the bright cherry red skin that light-skinned folks who get carbon monoxide poisoning get). One can reverse this either by sticking the parties in a hyperbaric oxygen chamber (exactly as is used for people with the bends or nitrogen narcosis) to forcibly replace CO with oxygen, or (in the days before hyperbaric medicine was widely available) by giving one methylene blue (which also has the fun effect of turning one's urine blue).
About the only one can suffocate from carbon dioxide is by being in such concentrations of it that it displaces oxygen to the point one would suffocate. It is pretty darn hard to do so; you either have to be practically huffing the stuff, in such deep depths that gas exchange of ANY sort is hard, or be on a planet such as Mars with almost no oxygen. (Dry ice is sufficiently safe that people have put hunks of it in coolers for food products, and even for organs meant for transplant. You have to have an awful lot of dry ice and a well-sealed room to successfully suffocate someone, and even then it isn't by displacing oxygen in the blood; rather, it's by displacing all other gases including oxygen in the air--in other words, instead of replacing oxygen in the blood, there's no oxygen to get to in the first place.)
One of the rare cases of carbon dioxide suffocation that does occur--some cases of SIDS or "crib death"--occurs largely in infants under six months old who roll onto pillows or on their stomachs (and often have some miswiring or under-maturity in the "oxygen sensor" part of their brains that tell them to roll over or gasp for air); this is why nearly every baby-care group nowadays promotes "back to sleep"--putting babies on their backs to rest. SIDS generally does not occur in infants over six months of age (in those cases that do, it is either a case of something drastically wrong with baby's neural wiring or something wrong with the parents mentally [sometimes Munchausen's by proxy] where the parents actually have suffocated the kid).
About the only way you'd die from carbon dioxide poisoning (in the amounts of dry ice it would take to cool a motherboard and processor--less than it takes to make "swamp gas" in a 55-gallon cooler) is by directly standing over the motherboard, having the computer sealed up and a tube leading out, and huffing the fumes from the tube. If you do that, you bloody well deserve a Darwin Award--please, get the hell out of the gene pool now, because you're making it skanky for the rest of us. :) With reasonable precautions (that do NOT include hazmat gear--mostly good ventilation such as computers should have anyways and heavy gloves if you don't want a nasty case of frostbite from handling dry ice) you should be OK. You've enough brains to know how to overclock the darn thing; surely we don't have to put "DO NOT EAT. CAUSES SEVERE FROSTBITE IF HANDLED WITH BARE HANDS. KEEP AWAY FROM CHILDREN." somebody-has-been-just-stupid-enough-to-have-done- this-and-sued-successfully warnings that most of the United States's population seems to require these days. :P
-Windigo The Feral (NYAR!)
Sometimes the lessons of history are worth looking at.
Remember the water-cooled mainframes? They had networks of heat pipes ducting heat from the chips to a heat-exchanger off the board. The heat-exchanger would transfer the heat to chilled water, which went to a rechiller of some kind. (Many buildings had cold-water systems for the air conditioning, so adding the computer into the building's chiller was a bang-easy deal.)
(Speaking of weird systems, I had the honor of reviewing for Federal Computer Week a military PC, the Deuce by C3 Technologies, which was a computer designed to land on the beach with a platoon of Marines. It was water-proof, sand-proof, and damn near soldier-proof. By necessity, the system case was sealed tight -- no air exchange with the outside at all. Instead, you had an internal fan and a double-sided heat sink that ported heat to the outside of the case. The "portable" computer weighed 33 lbs, most of it in the metal of the case.)
Take the idea of heat pipes to reduce "hot spots" and an active heat-exchange system -- and you can have a much-lowered thermal resistance for your system. Especially if you live where the air temperature gets over 110 degrees F.
All that I can think is that this is the computer equivalent of drag-racing, and can't really serve any practical purpose.
Bruce
Bruce Perens.
Now hiring experienced client- & server-side developers
-- @rjamestaylor on Ello
What Are Halons And How Do They Work? They are low-toxicity, chemically stable compounds that have been used for fire and explosion protection throughout this century. Today, Halon 1211 (a liquid streaming agent) is used mainly in hand-held fire extinguishers and Halon 1301 (a gaseous agent) is used mainly in total flooding systems. These halons have proven to be extremely effective fire suppressants, which are clean (leave no residue) and remarkably safe for human exposure.
Three things must come together at the same time to start a fire. The first ingredient is fuel (anything that can burn), the second is oxygen (normal breathing air is ample) and the last is an ignition source (high heat can cause a fire even without a spark or open flame). Traditionally, to stop a fire you need to remove one side of the triangle - the ignition, the fuel or the oxygen. Halon adds a fourth dimension to fire fighting - breaking the chain reaction. It stops the fuel, the ignition and the oxygen from dancing together by chemically reacting with them. Many people believe that halon displaces the air out of the area it is dispensed in. Wrong! Even for the toughest hazards, less than an 8% concentration by volume is required. There is still plenty of air to use in the evacuation process.
I consider myself newly educated. :)
[
What they don't realize is that alcohol is a dielectric - they could *soak* their mobo in the stuff without problems and get substantially better cooling too!
Alcohol is a really flammable liquid. I'm wondering whether it isn't rather dangerous to use it for cooling?
Imagine when circulation of the liquid stops and it starts to boil or something. Then, with many electric equipment around it, it looks to me like you're really *asking* for nasty accidents (computer on fire etc.)
Every expression is true, for a given value of 'true'
I've got a bottle of Stoli in the freezer now. Maybe I'll give it a try. Or maybe I'll just chill -- I've noticed that after a shot or two, having a slower CPU doesn't bother me as much.
InstaPundit! Ahead of the Curve Since 30 Minutes Ago
I've read the various stories about cooling computer components/motherboards down using insane ambient temperatures. Many of these guys forget a basic tenant of computer design: the temperature of the silicon die in each package is what is important.
The ambient-temperature specification quoted in the spec sheets take into account the thermal resistance of the packaging in order to keep the die within an acceptable range of temperature. If you keep the ambient temperature at the package at, say, 0 C, and the thermal resistance between the packaging and the cooling method is insanely low, then all components will run within specification and you can overclock until you run into race conditions in the processor itself, or perhaps in support circuitry.
On selected hot-running components like the processor, you might want to drop the ambient temperature a little bit more -- say to -20 C -- to compensate for the compromises that CPU makers make between thermal resistance of their packages and other considerations. The goal here is to run the hot die, not package, at the lower end of its temperature specification.
This does NOT mean that you should subject cool-running components to the same out-of-range ambient temperature, as the cooler-running dies will then be running outside of thermal specification envelope.
In this particular experiment, they cooled EVERYTHING on the motherboard, plus a video card and network card. In their writeup they say that they picked a cool-running card, as opposed to a heat-filled monster. The experimenters subjected all the components, perhaps ineptly, to the same ambient temp of -60 C. Even military components are designed to run above -55 C. Most commercial-grade components are speced to run at an ambient of 0 C.
The result could be predicted: The overclocking of the cool-running Celeron chip was sabotaged by the overcooling of the support chips.
Just my pair-o-pennies(tm).
I'd get top of the line chips and clock them faster than any such chip you could buy. That'd be the only reason for me. I'd also never trust an overclocked system, but that's just me.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
Funny that they didn't realize that putting the mobo in a plastic bag creates a thermal shield (air) around it! And air is the BEST thermal insulator, after vacuum. These guys must be pretty weak in physics, I figure.
Actually, putting the mobo in that bag should have increased the temperature around the CPU: I guess the fan was not deactivated, so it was turning inside a very limited space, which creates a considerable mechanical resistance to the circulation of the air. This, in turn, makes the fan itself overheat, and hence the CPU, too.
Really, really dumb....
Sigged!
Seth
$5 / month hosted VPS on linux = awesome!
Christ, I wear a hazmat suit just to run Windows!
2 1337 4 u!
Carbon dioxide is not toxic unless you are exposed to insanely high levels; it's one of the most common gasses in our atmosphere. You're probably thinking of carbon monoxide, which is toxic. One of the most popular uses for carbon monoxide is for suicide-by-car-exhaust.
My mom is not a Karma whore!
You can try it with -your- system if you want, but, as I recall from high school chemistry, alcohol absorbs water from the air. The -alcohol- is okay, but the real-world liquid isn't pure alcohol, it's alcohol/water mix.
(In other words, it's like water being 'theoretically' non conductive - it's okay on paper, but in practice you can't get pure alcohol, or pure water, right up against the motherboard.)
Also witness that dampening the bottom of the motherboard with the alcohol, as described in the article, did, in fact, short it out.
--Parity
--Parity
'Card carrying' member of the EFF.
I can just see the beer ad now...
"Hi, my name is joe and I have dual-proc 200MHz Bombardier sunk under the ice at the North Battleford Bonspieler and Overclockers Community Association and it's doing 3.2 Tflops. That's almost 5 Tflops in Metric (7.2 American, 8.30 in Newfoundland). thank you"
2 1337 4 u!
Try starting a fire in midwinter sometime... ;)
To reach the flashpoint of alcohol, whatever it is, you'd have to heat the alcohol by about 120degrees-F more than usual (assuming alcohol is
normally at around 50-70dF, this stuff was at minus 65dF, at -least- (that was the inside-the-bag atmosphere temp wasn't it?); making it, then, much harder to catch on fire.
Of course, if it -did- catch on fire, it'd be just as dangerous as any other alcohol fire, so, well, it wasn't exactly 'safe as houses' as it were.
--Parity
--Parity
'Card carrying' member of the EFF.
That's not what they told us.
I'll look up my course notes.
I did question them, but they were adamant about it being toxic. They couldn't tell me why though.
I've done a web search, and most of the information I've found just mentions toxicity due to displacement of oxygen from the atmosphere, as per my original post. The limits that are specified are either very high when reporting actual test results (in the 50% v/v range to kill rats), or are in the low-percentile range and explicitly stated to just be the highest limit allowed by the classification schemes used.
One reference mentioned acidification of the blood as an effect of high CO2 concentration, but only to mention that it wasn't significant in the few-percent range. It would probably be relevant at high pressure (e.g. for divers), but I'm not sure if it's a concern at STP.
Hmm.
Solubility of CO2 in water, according to Ye Rubber Bible, is just under 0.1 g/L, for about 0.002 moles/L. Water has a "concentration" of about 56 moles/L. This gives a relative concentration in water of about 3.6e-5 M/M, for a pH of 4.4 assuming 100% dissociation.
What is the minimum safe pH of blood?
Caveat: A pH of 4.4 is a worst-case estimate, as other dissolved substances in the bloodstream will make the CO2 less soluble (witness the effect of dropping salt into a can of Coke).
Um, C O2 (not C02 as you typed) is produced in normal mammalian cellular perfusion, and freed to the atmosphere every time you exhale. It takes a HUGE volume of carbon dioxide in an enclosed room, before it becomes a problem for further respiration. Your potted plants will thrive, as they take in carbon dioxide, and produce the free oxygen you need.
Frozen C O2 is called "dry ice," and is used to keep meats and dairy products cold in shipping. In normal room temperatures, it won't melt, but it will sublimate directly to the gaseous form, which, as stated above, is perfectly normal around we mammals. If you want some frozen carbon dioxide, go to an ice cream store and ask for a bag of it.
Dry ice, aka frozen carbon dioxide, is dangerous to handle. You need tongs or thick gloves. If you touch it directly, it'll freeze the cells of your skin and muscle tissue quickly, creating a burning sensation then killing the flesh. If you don't touch it with your skin, though, it's pretty forgiving.
This isn't like dealing with halon, or carbon monoxide. Halon is released as a fire retardant, and works by denying oxygen that fuels a fire. Carbon monoxide is a byproduct of petroleum burning, and reacts toxically with living cellular tissues. These are highly dangerous materials.
In short, carbon dioxide in its frozen form is slightly more dangerous than liquid nitrogen, is not as cold as liquid nitrogen, and has about the same health risks involved in breathing and direct contact.
[
Thank you, mister grade 3 science teacher.
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"You spilled my egg... I needed that egg."
Frozen CO2, also known as dry ice, is available from a lot of places. You used to be able to get it from just about anywhere that did a lot of food freezing, though they're a bit more stringent about selling it these days. It's not terribly dangerous, either; you're putting out CO2 all the time. You just need to have decent ventilation in the room. We use dry ice/alcohol mixtures in the lab all the time, and everyone agrees that it's more of a hazard as a freezing risk than from a poison standpoint.
It's also important to point out that CO2 is a powerful stimulant, so if it starts building up you'll get very twitchy and often start to panic. This will generally cause you to run out of the room, which is exactly what you need to do to save yourself. This is not an accident but an evolved survival behavior. Your body is also quite good at getting rid of CO2, so once you reach clean air you'll recover quite quickly.
There's no point in questioning authority if you aren't going to listen to the answers.