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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.
I wonder about the value of overclocking and pushing technology to the extremes in home computers, when the designers of supercomputers have realized that the performance gains achieved by pushing clock speed do not scale linearly with the cost. At some point a maximum speed will be reached and the cost of going any further will be staggering. The architects of high end systems have realized that massively paralell systems were the most practical way to obtain orders of magnatude increases in performance. I think that effort designing languages and programming pardigms to effectively use MPP architecture may be effort better spent than building fluorinert or alcholhol cooled overclocked systems. I suppose these systems are more akin to chopped channeled and supercharged 43 ford roadsters than to a 747 in terms of transporting people and cargo.
enough is too much
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.
Excellent points, esp. (1). When I first read their method, I thought, "Air is a great insulator; that'll never work." I was quite surprised when they said the MB was cooled, but your suggestion the probe wasn't mounted correctly is probably correct.
To reiterate - non-circulating air is one of the best thermal insulators. That's why home insulation is generally fluffy spun fibers. The material has many small pockets of trapped air, and the trapped air is the actual insulator.
These guys did the same thing. They had a bubble of air around their CPU inside the bag, which probably significantly reduced any cooling to be gained from the dry ice & alcohol
ShoutingMan.com
They did -not- pump all of the air from the bag. They even added paper tissues, if you have noticed.The paper tissue alone would add one millimeter of air layer, if not more. And they had more than that around the CPU, if you have noticed. And the temperature measured was probably not on the CPU itself, but on the plastic bag's surface (from the inside). -65 would be WAY too good to be true if it was measured on the CPU, the thermal gradient is, unfortunately, much higher. Even the overclocking results show it clearly that the poor CPU was sweating bigtime. I stand by what I said. You are wrong.
Sigged!
Actually, that was accurate. Halon-style gases chemically interfere with fire. Enough oxygen remains in the room to be fairly safe, with Halon it may raise your heart rate -- other gases have other side effects. In large computer rooms, whether carbon dioxide or suppresive systems are used, it is common to have gas masks (filters) or breathing apparatus (air tanks) in the area. Lights, sirens, and delays to allow evacuation are standard -- but also common are some masks in case getting untangled from machinery takes too long, or in case rescue is needed. Particularly if the cause of the fire involved someone getting electrocuted, and rescuers have to linger in the area.
I believe many liquors have small amounts of methanol in them....this is what is "purified out" when you hear about purified spirits. The methanol actually often gives flavor, but will get you sicker faster in large quantities and contributes greatly to hangovers.
Email me.
Don't trust anyone over 90000.
+++ATH0
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
Actually, sportsmen and food workers who handle dry ice routinely know that the simplest way to handle it with a little newspaper. A few layers of newspaper provide enough insulation for easy handling. When using it to keep your fish frozen you can leave it inside the newspaper and the cold will leak out. And squeezing the newspaper will show you that is not a good idea.
Um, you know when you exhale? thats CO2 right there, the stuff is not at all dangerous. also, the Frozen stuff is not that hard to come by, and can be used in regular coolers for keeping food cold (the stuff dosn't melt, it turns directly into CO2 gas)
I'm guessing this is a troll, but I thought I would respond anyway, you might have gotten C02 confused with CarbonMonoxide, which can cause problems.
ReadThe ReflectionEngine, a cyberpunk style n
"Dear woman, why do you involve me?" The overclocker replied. "My time has not yet come."
His mother said to the servants, "Do whatever he tells you."
etc. etc.
...the master of the banquet booted the computer that had been cooled with wine...
(Okay, this one was kind of a stretch.)
Ignorence is blis.
There are limits. Electrolytic capacitors become useless below some temperature. That temperature depends on the construction - which electrolyte.
Electrolytic caps are formed from two pieces of foil separated by an electrolyte. A chemical reaction forms an insulating layer between the electrolyte and one of the foils. The high value of capacitance is due to the very thin separation of the electrolyte and one foil. The other foil simply provides contact with the electrolyte.
Current flows through the ions in the electrolyte. That's where most of the ESR (equivalent series resistance) comes from. If the electrolyte freezes, there's not much movement of ions, and the ESR goes sky-high. Not much filtering going on then.
If you cool your motherboard too much, the power planes are going to get noisy. Glitch city.
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.
Now 10 liter of flammable liquids and electronic components that can spark or overheat (duh). That doesn't sound like something you would like to explain to the fire department.
Also the plastic bags is not a smart idea. Trapped air will reduce heat transfer, and a frozen bag gets brittle and breaks. Clearly the Fluorinert project was a lot better thought out (if only they had used dry ice instead of LN2).
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.
Well, presumably you would use a closed-loop system otherwise the alcohol would evaporate.
no, the problem was the person who started the thread wasn't funny...
ReadThe ReflectionEngine, a cyberpunk style n
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Why not just use like a 70/30 mix of anti-freeze and water? That would probaly got to about -60 I think.
Why the hell is anyone trying to do the WHOLE mobo? The only thing that gets really hot is the CPU. And what do we have next to the CPU, neatly bolted to it, yup a big heatsink. Fill in the gaps round the edges and add a couple of tubes to a cold source (even an old freezer) and you've cooled the hottest part instantly without having to p**s about with bags etc... Some people obviously want to have a writeup that everyone's gonna criticise.
Seriously, people are waisting all their money to "deep freeze" their CPU's and Motherboards to achieve speeds they can achieve with just $10 CPU and Motherboard fans.
I mean seriously, 500+MHz for a Celeron 333MHz is not a "GREAT" achievement. I have a Pentium II 300MHz that I have been overclocking to 450MHz for the last few years with just a regular CPU fan.
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.
As others have mentioned, excess C02 will result in symptoms of suffocation (even when enouugh oxygen is around), which means that you will be warned that something's up.
--
Linux user since early January 1992.
he said he got 550 air cooled... so the experiment only gained them 16mhz and yes you are either drunk or severely handicapped
"Mmmmm, alchohol-chilled computer."
Where do you get frozen Carbon Dioxide? And isn't that a little dangerous to handle? What happens if somehow it malfunctions and you get deadly carbon dioxide released into your room. Really, I'd love to overclock a Celeron 300a to 1000 MHz, but I don't want to have to be in a Hazmat suite to do it...
kwsNI
--
I wonder if my sister's Arctic screensaver would finally work.
"A little for the computer, a little for me! A little for the computer, a little for me!"
Ah, Simpsons.
--Lenny
What, me worry?
I did not know there was such a thing as solid alcohol.
| Ceci n'est pas une pipe.
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.
50 people post responses on an absurd statement about C02.
When death looks you in the eye, smile. Someone needs to cheer him up.
1) Air/nitrogen gas are poor conductors of heat. They act as insulators. Any heat transfer/cooling that took place during the experiment was minimal.
2) Freezing the plastic bag makes it brittle. It won't take much to crack the bag.
3) Motherboards are not meant to be frozen. I've seen plenty of experiments that try to freeze the whole mobo. Taking a motherboard to -60 deg C will ruin a board over long periods of time.
4) There are plenty of sharp objects on a motherboard to puncture a plastic bag.
5) Any parts of the plastic bag not covered by the liquid could be melted by anything hot.
They say that the thermometer's probe was placed next to the CPU on the motherboard. Was this on the inside or outside of the plastic bag? I have my doubts that the probe was correctly mounted.
They say the processor before the experiment was flaky at 566Mhz but after the experiment was rock solid at 566Mhz. Due to the poor system of cooling, doubtful.
Second, instead of just saying that we booted Windows and it didn't work, come up with a test suite that verifies different components on the mobo for functionality. For example, have tests that verify the pci bus, pci arbiter, keyboard/mouse controller, usb, ide controller, timers, ect... If you don't have these tests, Linux is a good place to start. View what comes up on the startup.
As a suggestion, insteading of freezing the whole system, go after the heat producing areas such as the CPU. Come up with a simple system for liquid cooling just the CPU and you have a winner.
That is 'Stolichnaya vodka' in case you don't know
Try chase your ice-cold Stoli with a beer. Watch the speed of CPU. / / / Incidently this reminds the a funny story. Many eons ago where 300bps links where the fastest once and only the managers were able to get those links from the company, my boss got the link and a dumb terminal, with a purpose to access mainframe-based operating system VM. VM terminal interface has never been designed for a slow links, so it worked like a shit. My boss finally discovered that drinking lots of beer slows him down so he's no longer typing that fast. Alas, he coudln't get the company to reimburse the cost of beer. Oh well ...
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
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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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Also, CO2 can disolve in alcohol. This provides a homogeneose cold liquid. I wouldn't go so far as to say that CO2 is not hazardous; solid CO2 has a temperature less than -78C, and can cause frost bite upon contact with skin. Also, CO2 is lighter than air, so sinks to the bottom of the floor (after it vaporizes), displacing the air that was down there. If the environment dies not have enough circulation, a person could pass out because of lack of oxygen, then end up on the floor where there is even less oxygen. BTW, water can be brought well below 25F by adding tabble salt (NH4NO3 works better). Also, antifreeze does not use normal alcohol, rather C2H4(OH)2, which has significantly different properties (let's not give anyone ideas about drinking antifreeze to get drunk).
Sometimes I've believed as many as six impossible things before breakfast.
It would have probably worked better if they used that fluorocarbon liquid stuff that somebody else used. Because it's nonconducting, you can immerse the components right into the liquid without having to worry about the insulating bag.
You clowns may be techy, but you obviously failed chemistry... Carbon MONoxide is poisonous. CarbonDIoxide is not even on the same planet as far as health risks go. Obviously you can't exchange either one for the 78% Nitrogen you need to breath, but CarbonMONoxide will kill your silly ass. I play paintball profesionally boys, and we fill the newbies all day long with that shit. Get a clue.... CO2 is fine for makeshift refrig...
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.
If I would take my laptop out for a spin around Pluto during a spacewalk, suppose; I would need to check whether it worked, wouldnt I?
Yeah, these guys are crazy I agree, but if NASA did this expmt 5 years in the future, it would make sense.
(The laptop busting, however should be reported to the SPCC)
SPCC- Society for prevention of crulty towards Computers.
Except for the post that "there's enough CO2 around to avoid fire risk", why wouldn't risk of igniting the ethanol (95%) by a spark by an issue. Alcohol fires are nasty. I've seen people permanently disfigured by others playing with Everclear in their presence. Can someone clue me in?
Just bring up here to Saskatchewan (Canada) its damn near -40 C 10.5 months of the year. You could save a lot in the price of that coolent. In the winters I just make a server room (a.k.a. igloo) out back and just string some cat5 back into the house through the basement window. Turn my 486/66 mhz into a 486/200 mhz!... Well not really, but I can dream can't I?
Last time I checked, 566MHz is a little bit more than 16 MHz more than 366MHz.
Either that, or I'm drunk and not subtracting correctly....
My plan is to pimp before they realize I'm a jackass. Hit 'em hard and fast.
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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Why not just put a small chunk of dry ice directly on the heat sink of the CPU. I would not put it directly of the chip, but on the prongs of the heat sink. When it melted on to the prongs of the heat sink, it would be kept it from sliding off. If this was done before the CPU was powered, I would be concerned that the die could actually be cold enough to prevent a successful POST. Once the cpu was powered up the heat should ballance out Another concern if dry ice was used would be water condensation from the air. Maybe sealing the area around the edges of the CPU and near by mother board with a non-conductive oil would prevent this.
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.
Well, in the C300a, i guess a combo of both would be good. But don't forget that all modern ones are locked. And besides, My PII350 is doing 133 just fine (466 total). At 133mhz fsb, you have a 1/3 divider AND a 1/4, so 2 options: PCI @ 44mhz (133/3) or PCI @ 33mhz (133/4).
Sure the AGP is now 89mhz, but he G200 is holding on. Higher fsb increases gaming much more than the multiplier (ie, ram is @ 133 too).
My C566 can hit 1ghz with 112fsb. It's the only way to fly...
Most folk'll never lose a toe, and then again some folk'll...
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.
If they actually overclocked more then 16mhz it would have been a decent showing... but damn...
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. :)
[
If I remember correctly, they ran Half-Life , not Quake with the high cpu speeds.
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303infinity Rocks, buy their CD's.
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!
CO2 is, in fact, fatally toxic to humans at concentrations of only a few percent (by volume) in air! I think 5% makes you faint, 10% kills you (approx.)
I'm pretty sure you're thinking of CO, which is pretty toxic (it binds to red blood cells better than O2, so even if there is oxygen in the room, you axphysiate quite quickly). CO2, IIRC, is quite inert.
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
Now, since I'm still running on my t(-t,+k??)rusty old 386sx, I'm kinda fuzzy on the idea but...
I heard some nasty rumors about some of these new fangled Pentoom Mommy boards having thermometers on them. From my experience writing programs in QBasic, I know that if numbers get too small, they can suddenly get big again.
It would be a real shame if these machines that are at -65 start thinking their temperature is close to that of the Sun (which, not to be confused w/ my Sun 3/60, which has no problems with heat whatsoever)
my sig's at the bottom of the page.
I read that a 1ghz Tbird will die in 8 seconds w/o a Heatsink/Fan
And I've seen pictures of it. The ceramic die cracks, and then yer screwed. I wish I had a link handy....
Simply because the L2 cache gets much hotter than the actual core, and when something on the same die expands (or in coldness, contracts) faster than the rest of the die, you get cracks. Not a pretty sight.
Most folk'll never lose a toe, and then again some folk'll...
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?
Bah, that just breaks an entire plot device in Terminator 2. If they don't need the gasmasks for the halon system in the office, the three wouldn't be able to take them and use them to avoid the teargas. Thanks a lot for shattering the illusion!
Note: This was a joke
Syllable : It's an Operating System
Nitrogen is the most common ingrediant in air. I apologise, it's been a long time since highschool chemestry. An interesting note, however, CO2 fire extinguisher systems a often built into computer rooms in place of water systems, for obvious reasons. I am instructed, if the system goes off for any reason to get out of the room immediately.
"..don't you eat that yellow snow."
I keep seeing these supercooling articles, and because some of you guys seem to know what you are talking about, I begin to question my own intelligence. Isn't the whole point of cooling to prevent the release of magic smoke? And to do that, isn't maintaining room temperature completely sufficient? I understand the challenge is to get the heat away from the chip with it's small surface area, but a dialectric liquid with a heat exchanger in a tepid bathtub would work as well as dry ice or !liquid nitrogen! Am I off base here, or has someone confused colder with better?
"Proximity to wonder has blunted our perception and appreciation of it" --Tim Hartnell in 'Exploring ARTIFICIAL INTELLI
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!
Too bad these two other respondants have no sense of humor. Maybe their clocks are real small and they suffer from P-envy.
"..don't you eat that yellow snow."
Seth
$5 / month hosted VPS on linux = awesome!
Despite what some posters have postulated, there is nothing really hazardous about dealing with frozen CO^2. It's just Dry Ice, and when a block of dry-ice sublimates, it just converts into CO^2, a natural byproduct of breathing.
The advantage to using Alcohol in this system is that Alcohol has a much lower freezing point then water. Eg, you can have liquid alcohol that's 25 degrees fahrenheit, a point where water would be solid.
Cars use alcohol as part of the antifreeze. Glycol-Alchohol is the stuff you usually pour down your cars gullet.
Finally, an excuse for pooring ice cold beer down my cd-rom without the messy haggle of getting drunk!
Friend: dude, were you drinking before you got here? you seem to be wasting all that good bacardi on your G4
Help me through college please!
You were impressed by a poorly presented lie?
In Australia there's an alcoholic drink called "SubZero" -- it's a kind of a fizzy, sweet, citrus-y lollywater usually used for getting sixteen year old girls rather drunk.
:-).
I was rather surprised to see a headline indicating that SubZero was the latest weapon in the overclocker's arsenal
"..for speed!
"..don't you eat that yellow snow."
Why don't we all stop trying to push as much juice as possible through our kit, and try instead to get exactly the same performance, but at lower power consupmtion which would be a far more useful and valid project. Image a sort of "OK, I still get the same number of MIPS on this kit, but by dropping the voltage and using this low power cooling system, I can overclock it still and use less electric!". Now that I will respect. But not this - hey guys, why don't we all just cut to the chase and flop 'em out on the table next to a ruler and see who has got the biggest? :-) (like every man on this earth I wish I had 12 inches - not this enormous thing I've got right now! <cue cymbal crash>).
Bruce
Bruce Perens.
It is obvious to me this quite a "cool computer" to have. Or as a teenager might say, "way cool."
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.
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).
I heard a story from one of our sys-admins at work about a friend of his who submerged his CPU in a bath of non-conducting mineral oil which was chilled to sub-zero temperatures. I love the whole cryogenic computing thing.
They pumped (most of) the air out of the bag, so there was no layer of air between the motherboard and the bag.. They measured the temperature ON the motherboard, not outside of the bag, and it was at -65C.
Never underestimate the bandwidth of a 747 filled with CD-ROMs.
Thank you, mister grade 3 science teacher.
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"You spilled my egg... I needed that egg."
eom
My mom is not a Karma whore!