Slashdot Mirror
New 3D CPU Water Cooling Method
captain igor writes "According to this story on Wired News, a new company launched by researchers from Stanford has come up with a way to layer a silicon network of tiny tubes on top of a microprocessor. The system then uses a solid-state motor (no moving parts!) to pipe cold water through the silicon network. According to the article, this system can handle 1000 watts (yes, a kilowatt) per square centimeter."
Now my PDA can wee-wee in my pocket.
"A microprocessor... is a terrible thing to waste." --
GeneralEmergency
did anyone else just notice a several minute long outage of /.
???
I'm still wary about pumping water into my computer. What if one of those microthin pipes were to burst? Then you'd get a microsized stream of water shorting out your not-so-micro-priced processor. I'll stick to windtunnels and heatsinks... maybe a heatpipe or two.
the level of technology is astounding, maybe they could scale it up to say cool a mechanical engine in an automobile or even an air conditioner ?
nah thats unpossible
Forget about the cooling, tell me more about that pump! /me googles electrokinesis ..
apparantly it uses osmotic pressure to drive it, how cool is that?
A computer without Microsoft is like ice cream without ketchup.
Reminds me of "The Diamond Age" by Neal Stephenson. There was a bit in there where a future super computer was hooked up to a pipe delivering ice. As the batch runs, ice is sucked through the computer at amazing speeds, passed straight through the CPU. and boiling water is delivered (in large quantites) at the bottom. Not what I would like for me home PC :-) Still, should make water cooled systems much more efficient.
I choose to remain celibate, like my father and his father before him.
I'm sure those enormous heat sinks in the G5s are just for show. ;)
how long does that take to cool down a beer thats been sitting in the glovebox all day?
...before someone at IBM notices their use of 'MicroChannel'?
This sig left unintentionally blank.
It's not a solid state motor. I dare say, there's no such thing. By definition, a motor turns, therefore it has moving parts. In fact, the word "motor" appears nowhere in the article, so I'm not sure where the submitter dreamt that up.
It's a solid state pump that moves an electrolyte through it using osmotic pressure.
-Todd
"The details of my life are quite inconsequential..."
Where are the frickin pictures man?! I want to see it.
NR
That is until one of those tiny pipes clog up with organic matter, or something.
Ack. Slashdot is being slashdotted.
We have found the solution for prescott!
This is pretty cool, and I thank the poster and slashdot editors for putting up the story. I just thought that this was funny:
:)
Apple, Intel, DARPA and Cooligy did not respond to requests for comment.
Well that includes just about everyone mentioned in the article, so exactly where did the information come from? I see, I'm reading a posting about an article about another article about information gleaned from a website. Oh, well at least they told me
If we put in a miniature steam turbine we can generate power to charge laptop batteries and perhaps add a steam whistle to the sound system. Actually, since I can't get any sound out of my laptop a steam whistle would be a nice addition!
From excellent karma to terible karma with a single +5 funny post...
/. is acting weird, so someone will probably have posted a similar idea, but ...
If you could figure out a way to sew this into material, then you could have some really "cool" (literally) clothing. I'm sure people like the Army would be very interested in a suit or body armour that offered effective cooling, esp in the desert where a system with a motor could be undesireable. I know it would be sweet to get a set of motorcycle leathers with something like this built in (those Texas summers get a bit toasty).
Cooling with water reminds me of primitive automobiles and their liquid cooling . Most of the energy of an auto is wasted HEAT.
,just google(optielectronics) but most are used for high speed networking. Optical buses are achievable in my opinion right now. Logic gates are another story.
Something new needed in chip technology. Moores law is about to END.
How about opical-electronic computer chips. Lets reduce heat ! These chips already exist
A typical stove top burner is order of magnitude 1000 watts spread out over around 500 sq cm: so were talking order of magnitude less than 10 watts per sq cm.
if I take a teaspoon of water an put it on a sq cm of stove top and it boils in far less than a second. really almost instantly so its probably like less than a tenth of a second.
Thus if this thing is going to not explode, the flow rate required to avoid boiling at 1000 watts /sq cm is going to be on the order of hundreds to thousands of teaspoons per second.
If I take a tiny swizzel straw and try to suck through it I cannot suck 1000 teaspoos per second. Since my ability to suck is probably within an order of magnitude of the cavitation pressure for atmospheric pressure water a pump trying to flow this stuff through an equally small crossecttion may not be able to sustain such a flow rate. And any on-chip pump is probably going to have a simmilar crossection for its fluid intake port. (off -chip is another matter)
unless this thing is actually flowing the water based on the steam pressure itself, I'm skeptical that this can meet the claimed specs.
but I assume these people aren't fools. Perhaps the science reporter slipped a few digits.
Some drink at the fountain of knowledge. Others just gargle.
another article at The Register had this info out at 08:37:00 Tue Oct 07 2003 GMT (04:37:00 Tue Oct 07 2003 EDT)
"Cool" technology nevertheless. Anything to reduce the size of heatsinks is appreciated. Plus Intel needs this - The P4's and Xeon's heatsinks are still soome of the biggest on the market (retail box, not OEM). Even AMD's Athlon 64 has a smaller heatsink.
OK - who stole my duct tape?
I wonder how long until we have nanotubes running all through the processor. There's a professor at my school doing research on 3-D photolithography, which would allow much more complex structures to be built out of crystalline silicon. This sounds like a good application.
This side up.
That is all.
We won't see anything from that because of all the patents they did certainly claim on this. Therefor nobody will produce these things except some tiny unkown company (Cooligy) and they (Cooligy) will fall as well. The technology will be forgotten - for good.
Considering the consequences of a little algea or whatever in tubes so small, I'm sure they'll provide the coolant(likely non-water) and perhaps even an on board Closed coolant system.
Considering the size of 3rd party coolants shown on site's like Tweak3d.net I wouldn't be suprised at all if the setups didn't look like some of ThermalTakes larger models.
If most of the tubing is kept in the in-die, and the motor is solid state (not sure what size we're talking about) then I'd envision something that would leak about as mutch as an air cooled system. hehe.
"Oh... There it goes... my brain stopped" - Ed from Ed, Edd, and Eddy.
start to mean 'no moving parts'? I don't get it. It's an electronics term. I daresay the regular pump I use for my fish is made up of solid-state matter too. Solid-state used to mean 'not using a vacuum to get an electronic effect' and that's pretty clear to me. But there were no moving parts in a vacuum tube either, so now vacuum tubes are solid-state??
Cool.
1000 watts (yes, 0.9765625 kibiwatts) ?
Actually, I wonder what the theoretical limit is on converting waste heat back into electricity in a laptop... would it be worth the extra weight? Even if it's NOT worth the extra weight, it might be fun to do it just because it can be done.
Off the top of my head, though, I'm not aware of any laptop-scale device for generating power from a heat source.
I hope IBM's lawyers don't hear about this.
The latest Slashdot meme.
Maybe this is what itanium needs to make it onto the desktop and into the 1U rack.
Stick Men
The article has a link to another story at Stanford. The water contains an electrolyte, Borax. The flow rate in the Stanford story is tiny, and the chip temperature rise is significant. The guys in the primary article must have significantly improved on this, if they're claiming 1kW capability.
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When the first supercomputer was built on Seymour Cray's farm by 34 guys with 1 PhD among them (a junior programmer) the key technology turned out to have been refrigeration devised by a kid from the Amana Colonies. Seymour spent his career fighting heat as he strove to get path-lengths between components smaller thereby driving up power density as the cube of his system's scale and speed. He most certainly would have approved of the focus if not the approach taken by the Stanford team.
Seastead this.
How much force would it take to burst a pipe? I would think that would be instant death for your cpu... imagine THAT for a blue screen of death -- "Sorry, your CPU has drowned. Go buy another one!"
stuff |
Couldn't the tubes be designed to use the heat to move the water?
Maybe they were testing the water cooled system, and sprung a leak, and slashdotted themselves.
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Put it in the main CPU, not just the GPU. That way we can get rid of the screaming banshees/cooling fans in our towers. (So you can leave your favorite p2p running overnight without the whirrrrrrrring)
A Kilowatt is equal to 1024 watts. No, no wait. I know this one.
Why not do a more radical case-mod? Build an aquarium and put the motherboard at the bottom. Remove all fans and put good heatsinks on. Have a longer SATA cable to the HD (and other peripherals) and put it outside of the aquarium. Fill the aquarium with a suitable clear liquid that don't affect the MB or electronic signals. Glycol?
Now I would have a passive glycol-cooled computer!
I wonder if this kind of cooling would work. I'm not sure how to calculate such things... Which is the best cooling fluid?
Ah yes, and if anyone know what the colored stuff in lava-lamps is, please tell me. Pouring some of that stuff in could make the case-mod very interesting...
)9TSS
So, I get the one kilowatt of heat out of the CPU.
Where do I put it?
One kilowatt is like having a burning torch. Not so easily disposed of.
This is an old technology... you can create a tremendous amount of attractive-looking vapor by emitting a bunch of hot air in the right direction. Although there's a short-lived burst of heat and light (and sound and fury), pretty soon, everybody is cool to the technology.
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Wow! Not only can I run Java on the
processor - it can brew it too!
I can't wait to get my NeverEmpty
coffee cup on ThinkGeek!
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Doesn't seem like it is a new idea...
Great Sott! What was I thinking?!
I think you underestimate just how much I just dont care.
A quick search revelas:
6,606,251
as at least one patent they have on this. Many figures, much details.
Love that name Cooligy. May I suggest they lock in celebrity spokesperson Coolio. Saw him on Hollywood Squares which means he is desperate and you can get him cheap. Imagine Coolio's cooing Cooligy's cool coolers.
You still have to do something with the heat, nano pipes will just move it from one part of the die to another. The article makes no mention of radiators or heatsinks which will be needed to take the heat from the chip and dump it into the surrounding air.
Once you add a conventional heatsink to the mix this just becomes another aid to better cooling efficiency - like using a copper cold plate or thermal paste.
is it just me or is anyone else concerned about the increasing heat generated by current processors?
now that water cooling seems to be getting standard for cooling our great new opteron/p4 with about 100W power dissipation how long will it be that we need to cool our pc with liquid nitrogen just to be starting windows?
but on the other hand its kinda cool to know that your next gen processor could make you a cup of coffee in an instant
lp
-- Karma: beyond good and evil - mostly affected by posting political
my post erred because the reason the water boils is not the heat flux but the stored heat in the stove top coil. The transient delivery of this stored heat vastly exceeds the rate of power delivered to the stove and thus the water boils fast. but this would not be sustained.
I withdraw my original answer.
Some drink at the fountain of knowledge. Others just gargle.
While I think this is a great step forward in terms of cooling, I'm afraid that if this gets widely implemented, it'll end up making processors less efficient in terms of heat management.
A modern processor creates around 60-70 watts of heat. Heat management is currently a problem in many systems, and the fact that the processors convert so much power into heat creates a need for larger power supplies. Now, if this was to be widely implemented, the incentive for reducing the heat waste in the processors would be largely negated, which would result in even higher power requirements and so on.
In my opinion not a good vision of the future.
Tracert hops through VA/DC waaaaay too much (but it always does), then gets to WA state.
I get some slowness at cable&wireless in CA, then it hits Exodus (66.35.192.0/18) and just dies. Somebody go beat up Exodus...
All's true that is mistrusted
A semiconductor chip won't work if the temperature gets too much above 100 C. Therefore, by definition, you would be stuck with a very low power generation efficiency.
Your efficiency is limited by trying to extract work between the (say) 100 C CPU and the 25 C ambient environment. I'm too lazy to look it up now, but I doubt that you could recover more than a single-digit percent of your input power in this situation. What's more, even if you try to extract power from low temperature differentials, you tend to need very large equipment to do it. Not a good fit for laptops.
A Peltier type cooling element will generate electric current given a high temperature gradient, and is small. The amount of current though is very small :)
Hooray! The dawning of a new era! A physical design that destroys entropy and creates information!
They claim the potential to move 1kW through this surface, but they don't mention the conditions.
If you make it really cold on one side, and really hot on the other this could happen by itself.
Think of your cooler, it doens't leak heat much on a cold day, but on a hot day it will warm up much quicker.
Change your temperature difference, the heat flow rate will change.
On your boiling water, take steady state water evaporation vs energy input. Your 1kW Burner isn't going to be boiling thousands of teaspoons per second. You have to heat it up to the boiling point, then apply the energy to vapourize it.
Energy=Power*time = Mass * Heat of vapourization +Mass * Temperature Change * Heat Capacity
More people should take physics.
The engineering problem is getting Thot to be the microprocessor temperature, not the exiting cooling water temperature - this would give you much better efficiency, but at the possible cost of cooling power.
It's not wasting time, I'm educating myself.
Too bad I cannot go...
BTW, WTF is up with
Check here
As you well know Laptops have long have problems with both power and cooling. The power problem is coming closer to being solved with the advent of the fuel cell. As a by product of hydrogen and oxygen molecules combining and leaving behind their spare electrons, H20, or water is produced. Now I may be just a lowly computer science student but is it not feasible to collect these spare water molecules in order to further cool our overheating processors and onboard graphic chipsets using this cooling method?
I was working on a project in the early '80s to make ink-jet nozzels (pumps) in VLSI. We had a lot of nozzels on a single VLSI chip that could move ink very rapidly. All the logic and such was also on the chip. The pumps worked very efficiently and consumed very little power. They never seemed to get clogged either. This may be a nice new application for an old technology.
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As they were too busy chanting: 'IPO! IPO! IPO!..'
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Don't go there. It's goatse related.
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Didn't the computer industry take over watts yet? Shouldn't that be 1024 watts?
or
Insisitive clods! They should say 3412 BTUs!
You quitting proves that the karma kap worked. The most annoying of the whores shut up. --CmdrTaco
Peltier's cell. (can exchange voltage into temp difference and opposite) But you'd need a decent cooling device (radiator? Water cooler?) on the other end. You can't generate energy from heat itself. You can generate it from temperature difference (and thus heat flow) though. Plus this would impair heat dissipation, rather undesired with processors. You surely wouldn't be able to build a perpetuum mobile like cooling system (powered only by CPU heat, the hotter the CPU, the cooler theother side because water runs faster, cools the cell better, cells produces more energy so water runs faster ;) but -might- (considering all "overhead" heat produced and energy used by the devices) provide some savings.
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"The system is powered by a small, solid-state pump that uses a unique "electrokinetic" process. With no moving mechanical parts, the pump electrically generates osmotic pressure in an electrolyte" The Hunt for Red October is on! Now it uses a caterpillar drive to cool its computers, too. Prepare to be Ownzed in HarpoonIII, Connery!
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1000 Bits= 1 byte
IBM might sue over the use of the term "Micro-Channel." Then again, they might just want to forget that whole thing ;)
There exists no way of exchanging information without making judgments. --Bene Gesserit Axiom
This site has a few pictures which illustrate this new cooling technology.
You got a problem with kool-aid? It could be used to cool your computer someday.
Of course, you get any impurities in there and PFFFFT!
They say the first thing to go is your penis. Well, it's either that or your brain. I forget which...
I'm pretty sure a kilowatt is actually 1,024 watts.
Though, I suppose that's depending on who is measuring it. Not to mention that some electrical systems cannot handle larger wattages, or do so through Logical Wattage Access (LWA).
;)
-- clvrmnky
Hey look, I use my computer now for everything, I don't even need light bulps or a heating!
Not so, you could link the nanotubes to larger "arterial" and "venal" tubes to move the heat off-chip totally, then have another heat exchanger where the primary cooling circuit is cooled by a second water circuit, which because there's more room off-chip could be a flow of tap water in and water passed to a drain on the way out. This should prove pretty effective.
"'I pass the test,' she said. 'I will diminish, and go into the West, and remain Galadriel.'"
- JRR Tolkien.
Divide the volumetric flow rate by the cross section of the tubes. An excessive rate might exceed the capacity of the 'pump' or erode the tube sidewalls. I didn't RTFM, so I don't know.
Someone will have to doublecheck this for me, but I seem to recall distilled water as being very likely to damage any system due to simple chemistry. Last I recall from high school chem was that impurity concentrations will travel from highest to lowest, and that if the metal involved has enough of a charge to it, it'll just leach out into the water resulting in local pitting of the metal (and eventual failure of the surrounding structure).
Other then that, isn't it more of a matter of finding the right liquid vis-a-vis thermal density vs. size of liquid molecule? I bring up the latter as I recall reading that the size of the molecule vs. the diameter of the tube (hydrostatical effect?)
Pity about the fishtank cooled processor. It'd keep the tropical fish nice and toasty. In a pinch you could always short out the board and have dinner available pretty quickly I'd figure (anyone have any ideas on how fast it'd fry fish?)
I don't believe in the Grammar Fairy.
Can you imagine what you'd get with a Beowulf cluster of these?
A drinking fountain!
It might seem trivial to keep a heatsink well below cpu temperature, but it definitely is not. With coolant exiting the CPU and 70C, and a heatsink at 45C, the efficiency of this energy-regenaration process would be small. (well under 10%). In this very same example, the heatsink would have to be twice as large compared to a heatsink at 70C, in an ambient temperature of 20C.
Although the concept is basically valid here, it would be very impractical to implement. The space used up by the oversize cooling system could be replaced with more batteries, providing a longer battery life at similar size.
I've always wondered how these work to generate electricity from heat flow...
I assume a tiny amount of flowing heat is absorbed and converted into electricity? If not, then where does the energy come from?
What happens when you sandwich these cells? Wouldn't you get electricity from each cell, until the heat is completely absorbed?
And if that is the case, then wouldn't a sufficently well designed array of these allow you to reabsorb nearly all waste heat and recycle it back into electricity to be re-used in a closed system? Assuming a closed system completely surrounded by these cells and stacked thick enough to absorb nearly all heat?
Since this is probably impossible, where is the error?
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Ahem, most of the modern big iron and data centers in general have gone to air cooling so this is a bad example. In fact the problems with maintaining the chilled water system and the cost were the big factors in going back to air cooling but this is also an issue of reliability. Chilled water had a high of a failure rate.
I for one think if it is internal to the box okay but trying going outside the box with water based heat rejection will be a disaster.
Heatpipes have been around and used in laptops and GPU's for a while.
8 &oe=utf -8&q=heat+pipe+cpu
Yeah, the heat dispersal is extrodinary. But, I am certain when the end-user product arrives it won't be flawless. Perhaps not as functional.
Heatpipes for every day of the week:
http://www.google.com/search?hl=en&ie=utf-
This is not very relevant, but I can't resist the comparison. I work at a nuclear reactor, a small one that generates 250 kW at full power and is about the size of a washing machine. Now, it has way more than 250 square cm of surface area, so at 1 kw of heat dissipation per square cm this stuff could easily keep it cool. Of course we already have a better cooling system involving a 25 ft deep pool of water, but it makes an interesting comparison when you think about what kind of heat a CPU is actually generating.
Stanford is such an awesome university! Look at where all of these Cooligy guys got their undergraduate degrees:
Founders:
Ken Goodson - BS in Mech Eng from MIT
Tom Kenny - BS in Physics from University of Minnestoa
Juan Satiago - BS Mech Eng from University of Florida
Management:
Dave Corbin (President) - BS EE from University of Kansas
Dan Lenehan (VP Bus Dev) - BS EE from New Jersey Institute of Technology
Mark Much (VP Engineering)- BS Chem Engr. University of Colorado
Andy Keane - BS Physics Rensselaer Polytechnic
Board of Directors:
Dave Corbin (see above)
Todd Brooks - BS Chem Engineering from Texas A&M
Rob Chaplinsky - BS University of Waterloo
Carl Everett - BA Business New Mexico State University
Len Rand - BS in Building Sciences, Rensselaer Polytechnic
Dr. Albert Yu - BS EE CalTech
Stanford is really an awesome school, check out this review
Gramar Fairy,
You said, " The easiest way to remember it until its habit is to substitute the full phrase in your (not you're!) sentence, and see if it works:"
In that sentence, you mixed up the common homonyms (male labia) "it's" and "its".
The word "it's" is a contraction of "it is". the term "its" is a the possesive form of "it", which is wrong unless you meant to imply that one must train the word to know "its" place in the sentence; in that case you would be correct but un drugs or maybe snorting too much fairy dust and ranting about ficticious male genetalia (homo = man, nym from nympha = labia minor.)
Some drink at the fountain of knowledge. Others just gargle.
powerbook g5 possibility? mwhahaha! everything is falling into place as planned..
Anybody with a clue want to compare and contrast this with the coolchips.com technology?
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"That's why power plants use steam or gasses heated to hundreds or thousands of degrees to run their turbines. " Isn't the steam just there to spin the turbine? You know, steam forced out by high pressure?
Yes, and the high pressure is caused by the large difference in temperature between the incoming steam and the condenser at the outlet. No big temperature delta -> little pressure -> not much work.
Rocket motors dont have moving parts.
Other than the ability to direct 2.5 million horsepower worth of thrust.
Not a motor indeed.
Maybe I'm crazy or have the physics understanding of a dead monkey, but doesn't thermal energy radiate or is that merely a function of heat transferance via matter? Also I think you would lose some energy due to electrical resistance assuming you weren't using perfectly efficient superconducters. ----- On a long enough timeline, everybody dies. -Tyler Durden
Guess what? All of a sudden your harddrive and your PSU sound like turbines while trying to get shut eye. The battle never ends.
No! It's heat TRANSFER that gives the electricity. So if you put the cell on top of dry ice block and put a pot of boiling water on top of it, you have 100C on one side and some -30 on the other, and the cell provides some electricity because some heat flows from the pot to the block, water cools, ice evaporates. If you stack two of these, you get some 30C between them. Combined they will provide stronger current, but because the temperature difference is lower, the voltage will be lower. (or something like this). The error is that the heat is not absorbed/cumulated in the cell, but dissipated on the other side. It's like potential energy of a charged particle between two objects charged with opposite loads versus energy of the same particle between one charged object and infinity.
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The capacity to move the heat off the chip will be dependant on an external system. That will be (as it is now) the bottle neck. It wont actually matter how fast the nano tubes can move the heat around. As for a flow of tap water, not only is the environmentally untenable, tap water contains all kinds of impurities (including biological). There is a very good reason for water-cooling rigs to use a combination of deionised water and various chemicals to prevent corrosion & growths.
Engines impart motion by the conversion of chemical energy. (ie, fuel).
For instance, although most of us refer to the thing inside our car as an 'engine' (internal combustion engine, to be more precise), if you watch NASCAR, they commonly refer to them as a 'motor'.
Your argument is basicallyor, for those Simpson fans:
Build it, and they will come^Hplain.
Ah, somone catches the GrammarFairy at its own game! It looks like the dust works, good job! Still, I'm not sure what source you're finding your definition for homonym. Here's some help from Dictionary.com: http://dictionary.reference.com/search?q=homonym&r =67
-GrammarFairy
You miss the point. While you definitely need a very pure coolant for flowing through the on-chip nanotubes there's no reason why that circuit can't exchange heat with a secondary (but entirely separate) circuit. If you think it's environmentally untenable to have a continuous flow of water just have the secondary circuit running from a millpond or tank in the garden (with a decent filter); that wouldn't be too expensive and a pond could provide a sufficient heat sink for any purpose, dependent on the size of the pond. Obviously we're not talking about something you'd want to do when overclocking your P4, but for insane chips where you're trying to dissipate a kilowatt per cm^2 this seems a perfectly valid method. It's very like the (real, in-use, current, present day) two-stage method used to cool nuclear reactors, go read up about it some time.
"'I pass the test,' she said. 'I will diminish, and go into the West, and remain Galadriel.'"
- JRR Tolkien.
No your the one who is missing the point! It doesn't matter how fantastic the nano pies are at moving heat, it still has to be disapated somewhere.
Once you start using a conventional heat exchanger, be it heatsink & fan or elaborate water cooling your dependant on that system to remove the heat. Its that system that will make the biggest difference to the die tempreture, NOT any fancy on die nono tube heat spreading technology.
Well naturally. But if you want a single-stage network of coolant-filled nanotubes with an external to-air heat exchanger, and want the whole thing to be big enough to remove a kilowatt (assuming 1kWcm^-2 and a die of 1cm^2), that's going to get very expensive. Air is a pretty poor sink. However, you could have a much smaller primary nanotube system exchanging heat to water at external ambient temperature and it would be much cheaper. The heat that water then acquires can be dumped to the atmosphere later, once it's been drained to a large pond or the drain. I think what you're saying is that said nanotubes aren't some kind of magic solution that can remove unlimited amounts of heat: fair enough, I'd agree with that. What I'm saying (perhaps what I've been thinking but not actually writing down) is that these could provide a mechanism for getting coolant to all parts of the chip, possibly even inside it with future lithographic techniques, and therefore potentially doing a better job than a conventional heatsink which will be some distance from the lower surface of the chip -- but that if you're removing as much heat as the article suggests you're going to want a two-stage circuit to reduce the cost of all those nanotubes (I don't imagine they will come cheap).
"'I pass the test,' she said. 'I will diminish, and go into the West, and remain Galadriel.'"
- JRR Tolkien.