PC Modding

[tansis]

Here's a stray thought from pit of anarchy that is my brain,regarding
the eternal struggle between the quest for a silent PC
and the dark desire to tweak the Bios and overclock,
thought I would share it with you all here...

Closed loop liquid cooling of electronics has been around for some time using a variety of different fluids, but all using mechanical pumps.

Could a ferromagnetic fluid be used as a coolant
in conjunction with a magnetic induction field pump?

A brief search of the web would suggest that a fluid
with a suitable working temp/ Curie point is feasable.

How the computer inards would react to the magnetic field
required to circulate the coolant is less clear to me.

Workable or crackpot ?

 

[zachtheterrible]

Magnets and computers DO NOT mix. Its the harddrive that will get screwed up by magnets (im not sure if thats the only thing). Unless there is some way of shielding it, or you have the magnetic pump far enough away that it wont effect the HD.

im not sure if ferromagnetic fluid is magnetic, but if it is, that makes things even worse.

 

[bmcculla]

You should look into heat pipes. They use wicking, evaporation, and condensation to move tons of heat without any moving parts. Laptops use them to move heat to the heatsink in the back of the machine. You'll still need to have a big heat sink to get rid of the heat without a fan.

 

[tansis]

Quick research online yields a solution to the problem of
magnetic shielding and a commercially available alloy sheet,
Ni: 80%, Fe: 15%, Mo: 5% plus trace amounts of S, C, Mn, Si, & P
would appear to be suitable, and relatively inexpensive.

Wether it could provide suffecient attenution depends
upon the frequency of the pump coil / coils?
(still looking for a working design / example on the web)

Thermal transfer between the coolant and the chipset through the alloy will now have to be considered. As well as the radiator side.

 

[zachtheterrible]

i knew there had to be some kind of shielding.

 

[jrz126]

I recall seeing a program on tech tv where 3m came out with this non conductive liquid that they submerged the entire motherboard in. no heatsink on the CPU and you could see the liquid boiling around the cpu. (I cant remember if I saw it or a friend told me about it, so it might not be true.)

I dont know why people want their PC's quite, I like sitting next to an airplane. :?

Those heat pipes on laptops still have fans, they only kick on when it gets super hot though (at least my dad's laptop has one.)

Also, have you put any thought into the powersupply fan?

 

[magickaldan]

If i recall correctly the liquid your referring to is Vegatable oil.

 

[bmcculla]

Distilled water is also nonconductive. If it was boiling it probably wasn't water or Vegetable oil. 100C is a bit hot for a comercial processor and oil would be even worse. Maybe Alcohol?

You need a heat sink for all these cooling solutions , liquid and heat pipe. You are just moving the heat to a more convenient place to dump it. You don't nessesarily need a fan you just need a really big heat sink.

 

[jrz126]

but a fan is more effiecient to get the air away from the heatsink, it's going to be closed up in the case so it's hard for the air to circulate.

just thought that I'd mention, copper is better at transfering heat through surface contact, and aluminum is better at disipating it to the air.

 

[evandude]

the liquid they use for submerging computers is some really expensive stuff made specifically for cooling without shorting electronics... to get enough of it to submerge a motherboard would be somewhere in the realm of several hundred dollars at least. not to mention, i'm pretty sure that it is highly evaporative so you would have to keep it pretty well sealed so your expensive liquid didn't evaporate away :lol:

hard drives are not THAT susceptible to magnetic fields. they are housed in a metal case, that's got to count for something... and you have to remember the weakness of a magnetic field when it's 8" or more away from the source... i know of people using hard drives in car computers and having them right next to subwoofers (huge magnets and electromagnets in there) without issue. not to mention using some shielding material, and you should be fine.

i would, however, question the thermal transfer characteristics and heat capacity of the liquid in question, as well as the price... and of course also the rate at which the pump can pump it. the flow rates in water cooling setups for computers are quite high (hundreds of gallons per hour), much higher than you might imagine; those pumps are a far cry from little piddly aquarium water pumps that are their closest relatives.

it would certainly be cool though!!

 

[jrz126]

isnt water one of the best heat transfer mediums because of it's high specific heat? if there was a much better liquid, wouldnt it be used in houses with hot water heat?

 

[evandude]

it is. but it also happens to be practically free. a slightly lower specific heat might be worth it if there are other benefits to a different liquid... ie- not being conductive, or being ferromagnetic as this thread is about so it can be pumped silently and with a different method.

 

[DirtyLude]

Actually most people just use mineral oil.

**broken link removed**

 

[gerty]

I need one of them on my desk :lol:

 

[Phasor]

Distilled water is also nonconductive.

I refute this statement - pure water, distilled water, whatever you call it, whilst in liquid form, will conduct electricity. True, it is less conductive than impure water, but nevertheless is still conductive.

The molecules of pure liquid water, at room temperature (25 degrees) and pressure (101.3 kPa) will split into hydrogen ions and hydroxide ions, at a concentration of 10^-7 mol/L (which is what is meant by "pH 7"). The presence of these ions causes conductivity. You could stop the creation of ions by freezing the water, but then it would be no good as a coolant :roll:

(For the non-chemical engineers around here, "pH" is a measurement of the concentration of hydrogen ions in a substance, whereby the pH is the negative of the log of the concentration of hydrogen ions. eg, a given a hydrogen ion concentration of 10^-4 mol/L, the log of that is -4, and the negative of -4 is 4, so the pH = 4)

As I understand it, the most commonly used direct coolants for computers (as used in supercomputing for many years) come from a family of chemicals known as perfluorocarbons, aka PFC's. These are carbon chain molecules, whereby the hydrogen side groups have been replaced with fluorine atoms. In particular, perfluoropentane (C5F12) and perfluorohexane (C6F14) are used in sealed systems, for cooling of electronics.

 

[dak246]

What if he used an external hard drive and took his internal out.

 

[plot]

i frequent a computer mod forum... and someone there recently put his motherboard and all it's components (including the water cooling stuff on it) directly inside a mini fridge, his temps are down to 4-5degree's celcious :lol:

he covered the components with something first to prevent moisture from wreaking havok, we've already fully explained to him that it's going to put to much stress on the compressor of that poor little mini-fridge and fry the thing. i've seen more then one settup have the water cooling hoses go into a minifridge and back out... most of those that actually worked though had a box fan behind the minifridge to keep the coils on the minifridge cooled enough.

i've also seen someone from alaska run a line directly outside his house :lol:

and i think it was some bloke from england that decided to try buring his computer 6 feet deep into the ground or something ridiculous like that... i don't recall if that one actually worked.


I really doubt the magnetic stuff is a good idea though, my friends computer was extremely flakey one time... and when i was going to look at it i noticed he had magnets all over his case. :shock: took those off and he never had another problem with that computer.