Liquid Nitrogen Cooling at Home?

newell98 asks: "Given the rise in popularity of water cooling systems for home computers, I was wondering how many slashdotters have played with the idea of cooling their system with liquid nitrogen? Lots of super-comps use them (or used to at least), and I'm curious about who's played with the idea of taking home computing to the same level?" The thing to remember about Liquid Nitrogen is that this stuff is generally not safe for home use. It must be stored and used with care or serious injury can result. I think this is why not-too-many people use such in overclocking. Water is by far more easier to obtain and is harmless to boot. Now, after saying all that, have any of you tried using liquid nitrogen in cooling a home or garage-built computer rig? What kind of safety precautions did you take, and how well did your cooling system work?

First nitro-cooled post!

[billcopc]

Seriously, this is overkill. Excellent cooling can be achieved with a traditional water pump and thermocouples (TEC's, Peltiers, whatever). At least that way you don't risk freezing your fingers off.

Just one problem

[caedes]

The major problem I can see with liquid N2 cooling is the formation of condesation on the CPU cooler. As soon as one drip hits the Motherboard the whole computer is out. :-( Water doesn't have this problem because the temperature is always above room temperature. So condensation cannot form.

Give me a break

[NickDngr]

For the cost of the liquid nitrogen and the precautions needed to handle it safely you could just go out and by a faster CPU and motherboard. You're not running a supercomputer.

liquid nitrogen safety and you

[StandardDeviant]

Speaking as a chemistry major who's spent entirely too much time in lab screwing around with the liquified gases, don't worry. Seriously. I mean, I guess unless you didn't have _any_ ventilation in the room where you were fooling with it. Still... You can hold liquid N2 in your hand, no problem. (there is an interface layer where your body heat has converted the N2 liq->gas, so it's "floating" on a cushion of gaseous nitrogen; basically just don't try to drink it or something retarded like that) I actually did the superconducting ytterium compound/levitating magnet thing once using superconductor pellets held in my hand with liq N2 poured on top. :-) So don't freak out, the liquified gases are pretty benign compared to some of the shite us chemistry f00ls mess around with... (as a still-not-so-evil example, 18+ molar mineral acids, so concentrated that they behave more like jelly than liquid) probably the only "liquid air" compound I'd be cautious around would be liq O2 and that's only because of the flammability aspect... I guess the main thing with these compounds is be careful about really really super cold metals because you could frostbite off of them (boiling, and thus gas interface, point is high)... wear work gloves or something if you're handling things in direct thermal contact with the gas (i suppose I should say liquid).

sorry for any incoherency or bad grammar/spelling; very, very, very drunk at the moment ;-) wot can I say, chimay belgian ale is a great way to celebrate a radical success day at work...

if you want to mess around with ReallyCold(tm) but don't have access to liquified gases, try dry ice + (alcohol, usually ethanol or something more esoteric than that but methanol would do in a pinch (non-chemist-speak: grab some dry ice from Kroger's or a party store and mix it with rubbing alcohol, waaaay colder than you'd get with normal ice and water. in a pinch, just find the cheapest nastiest grain alcohol you can... (everkleer, what?) ;-))). in lab I've hit the -20/40 F region using just dry ice and some not-to-uncommon alcohols. as I recall the F scale itself was calibrated using esoteric mixtures of dry ice and ethanol. which, if you think about it, highlights the total absurdity of the non-metric temperature system. always kinda wondered if the water-bases liquid cooling systems could be adapted to use this class of stuff as a coolant...

Have fun, and play safe! (which, with these compounds, really means don't snort the vapors or drink the liquid)

Safety is not a huge issue

[Mandelbrute]

I used to work with liquid nitrogen for metal testing, and it was also used to cool the electron microscopes. In a lot of movies, someone comes in contact with liquid nitrogen, then falls to the floor and shatters. Reality doesn't quite work that way. Anyone that has had a skin cancer "burnt" off with liquid nitrogen can tell you that it takes an uncomfortably long time to chill a small area of skin. I've had liquid nitrogen on my skin on occasion, and with breif contact it isn't the liquid that burns but any metal that the liquid has been in contact with. It takes a few minutes of immersion just to freeze a banana all of the way through. You just need to treat it with the same respect that you would treat a concentrated acid - keep it out of the eyes and off the skin.

The big safety hazard is if you have poor ventilation and end up with low levels of oxygen in the room. Another hassle is that the liquid conducts elecricity. The biggest problem, however, would be your PC icing up. Thermal stresses could also be a big problem.

Ultimatly, the question is why do it? If you have electronics that operate best at low temperatures then it makes sense, but PCs have components made to run at room temperature. Semiconductor behavior is temperature depenant, so the machine may not run as intended at low temperatures (the CPU may end up being made of a lot of resistors instead of transistors). Tin-Lead solder has known cracking problems at sub-zero temperatures, and not a great deal of strength anyway (Scott of the Antarctic got to stay there forever after the solder failed in fuel tins at low temperatures). Delamination of tracks from the fibreglass base could also be a problem if the board gets very cold - copper and fibreglass shrink at different rates.

All of these things can be designed around. the easiest solution that I can think of off the top of my head is a great big lump of metal in contact with a resivior of liquid nitrogen under a feeder tank. When the CPU gets too hot, drip in a bit more liquid - just keep the liquid a long way from the CPU to keep all the ice and water away. a watercooled block would, of course do the same job if somewhat less efficently - or my favorite: airconditioning, big heatsinks and big fans. That way the user doesn't overheat either.

Re:Bah

[Hadlock]

standard motor oil is non-conductive. so is synthetic oil. get a water (turned oil) pump, an oil radiator ($30 new @ autoshop), and some copper tubing. put fan on radiator (~8"x8"), and you're ready to go. kinda messy, but it works once you have it all in a closed system. you have a failsafe that if the pump dies, the computer still has to raise the temp of the oil above operating temp.

Re:a few liquid nitrogen safety points

[dattaway]

An unexpected hazard may be present with liquid nitrogen. Oxygen condenses at its temperature and may accumulate. Materials next to it may combust and explode next to this wonderful oxidizer.

Put an empty test tube in a flask of liquid nitrogen to collect oxygen. Then watch the pyrotechnic experiments of destruction...