IBM Water-Cools 3D Multi-Core Chip Stacks

An anonymous reader writes "Water cooling will enable multi-core processors to be stacked into 3D cubes, according to IBM's Zurich Research Laboratory which is demonstrating three-dimensional chip stacks. By stacking memory chips between processor cores IBM plans to multiply interconnections by 100 times while reducing their feature size tenfold. To cool the stack at a rate of 180 watts per layer, water flows down 50-micron channels between the stacked chips. Earlier this year, the same group described a copper-plate water cooling method for IBM's Hydro-Cluster supercomputer. The Zurich team predicts high-end IBM multicore computers will migrate from the copper-plate water-cooling-method to the 3-D chip-stack in five to 10 years." Reader Lilith's Heart-shape adds a link to the BBC's article on these internally-cooled chips.

Comments

3D cubes are nice, I guess

[krog]

But they're really gonna rev up performance once they move to 4-cornered time cubes.

But the question is....

[CowboyNealOption]

can it run Vista??

When will water cooling be feasible for ME?

[BadAnalogyGuy]

Water cooling is great for the bleeding edge enthusiast, but it's hardly an option for the workaday computer users. Laptops certainly could stand to use some better heat dissipation, and if water cooling through 50nm tubes is possible here, how long until it is both cost effective and size-effective for people who aren't interested in hardware for its own sake to see this type of thing offered to us, the average computer user?

And is stacking the chips better than laying them flat and in a strip (like Pentium M)?

Electrolysis

[mrbluze]

To cool the stack at a rate of 180 watts per layer, water flows down 50-micron channels between the stacked chips. I wonder what reactivity of water with the surrounding surfaces will do to the life of the chip. AFAIK pretty much anything that uses water has an inherent limitation to its life, owing to the presence of superoxide radicals and free hydrogen ions.

This will never work

[iamdrscience]

How can IBM be this stupid? You can't cool a stack of chips with water, they'll just get soggy. I know it's hard to be patient, but if your chips are too hot to eat, you're better off just waiting for them to cool down.

Basic Physics of Thermoconduction

[mrbluze]

I thought you would want something with a low boiling point so you can move the heat as far away from the source as possible? Something with a high specific heat is what's needed, which is why water is good. You can have any boiling point you like, depending on what pressure you apply to the liquid (boiling point is when vapour pressure = atmospheric pressure). If you are going to compress and decompress something to drive heat away, then use a gas.

3D CPU structure

[Lord Lode]

I always liked the idea of a 3D CPU with all the cores and memory interweaved through each other in a way to have the optimal short path for its purposes. A LOT of memory could be there right next to the CPU. It would be fast even without clocking it very high, so not even have to consume that much watts per layer. It's a crazy amount of watts per layer mentioned in the article btw...

It's quite the opposite

[mangu]

You don't want to cool with alcohol. The boiling point of most alcohols is between 60 and 80 degrees Celsius, as opposed to water's boiling point of 100 degrees Celsius.

Actually boiling removes much more heat than conduction. This is the principle used in heat pipes, where you want a low boiling temperature, because that will be the temperature in the hot side.

Re:Alcohol cooling is a bad idea.

[jeffmeden]

Only if you are making a wet/dry system, such as one that relies on phase change. If that's the case, it's refrigerant you want, and not alcohol (there is no real benefit to the vaporization unless the pressure swing is high). If you are doing closed loop all liquid, you want something that stays a liquid since vapor can't carry as much energy as liquid can given the same space. See automotive liquid cooling and refrigeration phase-change cooling for plenty of high-efficiency examples, none of which use alcohol or any similar substance.

Imagine the mistakes of the future

[kiehlster]

I can see it now, "IBM struck with class-action lawsuit after several incidents of computers being left out in the cold of winter cause the processors to explode due to the natural properties of water expanding into ice. Other incidents with water contamination in liquid nitrogen-cooled 3-D processors have resulted in a similar lawsuit."

IBM have done this before

[mad zambian]

IBM and water cooling of chips is not really new. I remember reading of some research they did back in the 80's when they etched micro channels on the back of processor chips, and forced water through them. IIRC, they reckoned they could eventually dissipate almost 1KW per square centimeter.
You want to drive bipolar chips fast, you apply more power. And end up with a piece of silicon dissipating way more heat per unit area than an electric fire. Mind you, so do Athlons.