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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.
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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 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/
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!)
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.
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!
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 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!