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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 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
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
I mean Moore's law still trumps overclocking any day.
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!
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