Hitachi's Water-cooled Laptop

surfacearea writes "The Register has an article about the new Flora 270W Silent Model, a Japan-only 1.8GHz water cooled laptop. Apparently the pump and piping is all held behind the LCD in the lid. I wonder how much extra weight that consumes." But best of all, it means now laptops have a chance to spring a leak!

Hmmm...

[Whispers_in_the_dark]

Okay, I can't read whatever language the informational site is in (I assume Japanese but I woldn't know the difference to be hones). However, I can look at the pretty pictures ang get an idea of what's going on. Two things occur to me:

• 1. It looks like there's a water pump in there. If that fails I assume you're going to have a toasty system (I'm assuming system shutdown would happen in that event).
• 2. Wouldn't there be at least a little bit of "sloshing" back and forth as the device moved around. I couldn't get a feel for how much water is in there but if there was enough I might think you would get some counter-motion there. Better bring the Dramamine for the laptop I guess.

I figure I'm off base on these but I figured I'd bring 'em up anyway and see if the same occurred to anyone else.

Re:Water?

[coreyb]

Pure (distilled) water is actually a very poor conductor. It's all the impurities in solution that make most "water" into a conductor.

Re:Less chance to overheat

[morcheeba]

Close, but not quite. The rate that heat is generated isn't a function of the cooling system; it's a function of the heat-disappating components (and, true, only a high-power processor would have a water-cooling system).

Given an insulated enclosure and non-stopable heat generation, the second best you can do is to evenly distribute the heat among all components (actually, the best you can do is distribute more heat to components that can take the heat - i.e. heat the aluminium just to the point of melting at the same time silicon reaches its melting temperature). A water cooling system would better distribute the heat (as opposed to when I did this- my poor little fan was running, but there was no air in my bag to move).

Re:Water?

[llamalicious]

Dude, pure, de-ionized water doesn't conduct electricity. Elec Co's use this type of water for spraying down the insulators on hi-voltage lines to clean off the accumulated grime (which does tend to conduct over time.)

I'm not saying they'll go that far in a laptop cooling system to filter water to such an extent, but it wouldn't suprise me.

Water is still bad for the components, but it doesn't always HAVE to conduct.

Increased Weight...not really

[SMQ]

For what it's worth, the Hitachi page lists the weight as 3.75kg, or about 8 1/4 pounds. (It's on the specs page, which is the second tab). That's only a few ounces more than my Dell Inspiron 8000.

Re:dangerous.. WTF?!

[Turbyne]

Did you event remotely think about this?!!!

airplanes, which have pressurized cabins

Aircraft cabins at 35,000 feet are not going to exceed sea level 14.7 PSI of pressure. You seemed to have misunderstood the term "pressurized." At 35,000 feet altitude, the ambient atmospheric pressure is considerably less than that at sea level. Furthermore, no animal can survive above 25,000 due to oxygen deprivation. Commercial aircraft pressurize their cabins to provide the oxygen density necessary to sustain life, as well as give some form of comfort to the passengers. However, to pump the cabin up to 14.7 PSI while it's only 5 PSI outside is not economical (expensive seals), and to do so would also put unnecessary stress on the aircraft (how many square inches of skin are there on an airframe? Multiply that by 14.7). To put it simply, you're mistaken in thinking that there will be increased air pressure while flying, compared to being on the ground.

It seems like the increased pressure might weaken the piping system

Even if you subjected the coolant system to increased air pressure, it would not weaken the plumbing. Water is an incompressible fluid, while air can be compressed. It'll take some serious PSIs to bust through a well engineered cooling system. Also, the technology of water cooling was invented during WW1, during development of fighter engines, so the technology has been proven.

If I get one of these, I'll use a vacuum case for travelling with it.

Bad idea buddy. Although the tensil strength of the cooling pipes would probably contain the liquid, but you'd be subjecting them to more stress. Without air pressure pushing in on the pipes, there's only the pressure of the water pushing out. The only concern I'd have with the cooling system regards the amount of power it would consume compared to fans. You can never have too much battery life.

Last thing - if you're really concerned, RTFM/RTFDS (Read the fucking data sheet)!
There's always a page describing the operating environments the device was designed for. A pressurized airplane cabin can be assumed equivalent to 10,000 ft altitude.

Fluorinert!

[Jedi Paramedic]

I believe the above-referenced liquid N2 cooling project [octools.com] (and others) used 3M's Fluorinert as their coolant medium.

3M has information on it here in PDF format [mmm.com].

Just don't drink the stuff, sounds nasty...

Re:Missing the point

[JebusIsLord]

Water cooling has already been used successfully in millions of Sega Dreamcasts and I never heard once of one springing a leak. It is nice because you can cool all the chips with one fan placed wherever you wish.

Re:Missing the point

[Buck2]

Heat is usually directly absorbed by batter. This, in turn, cooks it. There is a new book out by Alton Brown, reviewed on Slashdot today, that discusses just this sort of thing at length.

Perhaps you should check it out. I haven't read it myself, but I'm pretty sure that after a while you will come to the obvious conclusion that excess heat cannot, in any way, be used to extend the life of batter. (exotic Goldbergian contraptions which use steam to run a refrigerator excluded, of course)

HTH, HAND.