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Liquid Nitrogen Beats Air Cooling (Again)
joe094287523459087 writes "some guys used liquid nitrogen cooling via a cardboard tube to get a 20,000 3D Mark score. you can see the frost forming on everything - wouldn't the moisture from the condensation kill the board?" The Muropaketti guys had already done this with their microprocessor. Apparently the next step was to speed up their graphics card to match.
wouldn't any condesnsation freeze before it could short the electronics?
What's so special about him getting 20372 by overclocking his P4 to 3916 MHz?
The article has a picture showing that someone got 21504 by overclocking to 3998 MHz -- nine days earlier.
The boiling point of nitrogen is miles below the freezing point of water, so in the immediate vicinity you'd have some fast chilling and ice crystals. I'd be more worried about liquid condensation further away from the cpu, if it lowered the internal temperature of the case for example.
Unless they're venting vast quantites of boiling nitrogen into there though, it shouldn't be too bad. Plenty of hydrophillic stuff ariund should deal with that. A few sugar cubes in there, or some conc. sulphuric acid maybe!
Ok, so the Radeon has frost over most of its circuits. Is that dangerous for the said card? frost tends to melt into ... well liquid right?
I must be missing something, if someone could please fill me in...
how does one change his
The limiting factor in the performance of modern GPU's seems to be memory bandwidth. They were able to overclock the GPU itself a good bit, but not much on the video RAM.
We really need to see more memory bandwidth saving technology on GPU's. ATI pushed ahead a lot of cool things (early Z, occlusion culling, Z-compression, fast Z-clear), but it's not far enough. The Kyro/Dreamcast use tile-based deferred rendering rather than immediate mode, and the GameCube's GPU (designed by ArtX, which is now a owned by ATI) uses a 2 MB on-chip Z-buffer cache which alleviates the need to go to video memory every time they want to do a Z-test (which is typically at least once per pixel). Given, the Cube doesn't ever have to deal with a frame buffer bigger than 720x480, so a fixed size Z-cache is much more useful there.
On another note, I'd really like to see support for geometry amplification schemes (n-patch tesselation, displacement mapping, etc.) that work properly with stencil-buffer volume shadows.
Lex orandi, lex credendi.
Actually, if you touch liquid nitrogen for just a short amount of time, you won't hurt yourself. The heat from your hand vaporizes the liquid nitrogen that actually touches you, so you have a small air pocket between you and the liquid nitrogen... of course, if you hold it for more than a fraction of a second, it won't feel too good. One of the professors here actually poured some liquid nitrogen in his mouth and spit it on the wall during one of my classes, and he did it quickly enough not to hurt himself.
That aside, Liquid Nitrogen might be a bit of overkill here. When properly coated, I'm sure the parts are safe from the damaging effecets of melting, but everyone needs to remember one thing, heat is the enemy, it's obvious that it would take quite a bit to get too cold.
Obviously there isn't a future in Liquid Nitrogen cooled computers, but take the idea back from the "weird science" to the new liquid/radiator idea. I do believe silent machines running cooler with liquid cooling, will become a new trend.
Lastly, why does everyone brag about their 3DMark scores? If you suck at gaming the extra pixels sure ain't gunna help ya.
Ignore the "p2p is theft" trolls, they're just uninformed
Build a compressor/cooler.
If you could do it right, and can afford the proper parts to build it. Create a high-power compressor, and have it pipe super-cooled fluids continually through both processors. Therefore, you don't have to pour/buy liquid nitrogen everytime you want these results.
The problem is that it costs a lot and is quite difficult to build a fast high-power compressor/cooler. If you guys can accomplish this, then I'll be impressed. Pouring liquid nitrogen onto stuff to keep it cool isn't really that exciting/impressive in the long run, since it is far to manual, and doesn't require much thought to come up with the idea.
I am curious though, does anyone know of more fancy coolers for the processor that work impressively but don't require constant manual addition of coolant?
~ kjrose
That LN will take a while to evaporate once the container it is in cools down sufficiently. Physicists use cold traps powered by LN all the time. In fact, a friend of mine built a cyclotron that uses a 40 Amp magnet and he cools it with LN. He checks on it daily. It's pretty effective stuff.
Run the whole thing in an improvised glovebox filled with dry nitrogen gas at slightly higher than ambient pressure. Boiling liquid nitrogen results in large quantities of totally dry nitrogen gas.
:-)
Now the only problem remaining is how to avoid condensation on the glovebox itself so you can see what's going on inside
Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.
Well--eventually, maybe. But what they've build is essentially the back half of a water distillation system. The water that condenses out of the air will be very pure, and have a very low conductivity. (The resistance of a 1 cm path through ultrapure water is on the order of 18 meg--that's ohms, not byes--so it probably conducts no more electricity than the plastic of the board.)
Yes, the condensate will eventually pick up contaminants, and at the edges of the cooled region where liquid water is free to flow you're likely to have problems. The solution would be to keep the entire mainboard in a dry environment. Seal it in a box with only an inlet for LN2. The little bit of water in the box will condense out (on the N2 fill pipe rather than the board if you remove a bit of insulation) and as the LN2 boils off, the box will be filled with dry, inert nitrogen. As an added bonus, this will help suppress fires.
~Idarubicin
Have the guys on the ISS (or indeed any space mission/station) ever used the 'cold hard vacuum' of space to get their systems running cool and fast. You don't have the problem of condensation, you could make the sink a great big copper array (being very, very sure to always keep it out of the sun) and you'd enjoy even better performance (it's only about 3 Kelvin out there...).
I guess you'd run into problems with cosmic radiation - but nothing a good dose of shielding wouldn't fix. Placement would also be an issue, couldn't just pin it to the back of the station...
Anyone know of any experiments along those lines?
It's not that I'm Anti-American - I'm Pro-Freedom
I mean Moore's law still trumps overclocking any day.
It's really, really cold.
Bibo Ergo Sum.
Heh, yup. I had to watch a friend in 4th year physics dunk his fingers into and out-of liquid nitrogen really fast a few times before I was brave enough to try it myself.
As advertised, the flash-boiled liquid nitrogen insulates your fingers for a fraction of a second. You can't keep doing it though, lest your tissue cool down too much, and who knows *exactly* how slow/fast you can do it without injury, and no-one was willing to try and find out
Kind of to go with this, I found a (Finnish, sorry, but you can still look at the purdy pictures) page that has some interesting avi clips. These people got an infrared camera to do a few DivX clips on how the heat is distributed across the components. I like the first one best; they actually destroy an uncooled 1.4GHz Athlon Thunderbird. The CPU temperature rises to 300 deg C in about six seconds!
You can't shut us down! The Internet is about the free exchange and sale of other people's ideas!
When using rigour ways of cooling like just pouring LN over your board usually the capacitors give out first. Since they always attract moisture like crazy (remember those old radio's used to die because the capacitors were leaking electricity due to moisture in them?) there's always a small ammount of moisture in them. Now you don't want to have icecrystals forming in there. But still it's amazing what those boards can take. I have seen an old BX motherboard bent at an odd angle by someone pouring LN over it and still working. (Due to the immense temperature differences in the upper and lower side of the board the upperside folds inwards as material shrinks when the temperate is decreased) I guess the soldering is really done well. The same thing must have been happening at this chip btw. The underside of the GPU must have been warmer (a lot warmer) than the upperside so i don't want to even think about the massive ammount of material stress going in. ;) Well.... just keep up tweaking those GPU's and CPU's, it's always fun for us to watch.
but it seems like there should be some sustainable way of acheiving this kind of performance from these processors... could better cooling be acheived by increasing the pressure? anyone know how many atmospheres of pressure a P4 can handle?
from my knowledge, water created this way - ie condensation isn't yet ionised an doesn't have the ability to conduct electricity.
if many of you know the celeron [tm somewhere], the ppga grid is visible from the top of the chip and I myself have had water covering every pin and moving it's way down the board just to test this very idea of water damage.
[peltiers - not NO2] = P
fyi no damage was incurred and I was damn suprised.
- We seek not the answers, but to understand the question.
Sure, pure water is a bad conducting media, but that is offset by all those dust particles and soluble chemicals on the components. You can perform an experiment: Get a bottle of RO-water (reversed osmosis, much cleaner than distilled water) and pour in on your moderboard while running the computer. Se it short out. This particluar experiment has been carried out a few years ago. It is possible that the motherboards have become much cleaner since then, but I doubt it.