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Pc water cooling

  1. Nov 30, 2008 #1
    hey guys
    i'm thinking of building myself a pc next year
    and i've been reading a bit about water cooling.
    now every search i do tells me how great it is but the
    bit of me that spent 4yrs doing a mechanical engineering degree is a bit of a sceptic.

    firstly, sure, watercooling can deliver better cooling capacity in the confined space of
    a pc chassis. water has better conductivity and heat capacity than air and you can achieve vastly greater mass flow rates with water tthan you could with air!
    but where i get worried is where the the heat gets dumped from the system.:

    let me explain:
    one of the "benefits" i've read about is the reduced need for fans and thus you get a quieter system... but, if your processor is producing a constant amount of heat then you need that constant amount of cooling capacity to keep it at a constant temprature.

    now the watercooling system is going to take just as much heat from the cpu as air cooling plus the water also has the extra energy from the pumping, which needs to be dumped in the radiator.... and the radiator has to be air cooled.. so now instead of air-cooling the heatsink of the cpu, you're aircooling the heat load of the cpu+the added heat (or enthalpy) of the pump. thus you need more convective cooling in the radiator than you would have needed on the old aircooled heat sink in the first place? so unless your radiator is significantly bigger than your original heatsink you're still gonna need a similar or bigger fan.

    so really the only reason you'd need it is to keep your system significantly cooler (or at the same temp with higher heat output from the cpu) than would be achieved with air cooling but am i right in saying that you wont reduce your "fan" or convective cooling requirements?
    (of course the other reason is that it looks damn impressivE!)
  2. jcsd
  3. Dec 2, 2008 #2
    The only time water cooling is needed is for kicks. A properly designed and configured computer just needs a few fans. If you are up for the challenge and want to mess around then by all means, go for it!
  4. Dec 2, 2008 #3


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    With a large enough radiator you migth not need an external fan - it could just dump the heat to the room (as a central heating radiator does).
    Generaly the advantage of water cooling is if you either can't get enough cooling in to the CPU with fans - because of very high power output or a dense case, or you need a quieter solution - high speed fans are noisy.
  5. Dec 3, 2008 #4
    I've watercooled my PC before. Its fun. I used to overclock it also. Here is a pic of my old PC. (About 3 yrs ago)

    Attached Files:

  6. Dec 6, 2008 #5
    So, it sounds to me that the whole "water-cooling" thing is a scam and you're better off with a regular fan system. That does make sense to me. Who came up with the idea to begin with??? Did an engineer or just some computer hobbyist? You have to understand, most people in the IT field don't have your knowledge of physics and how the real world works. Try to find if there was any research done on this or if it's just some stupid idea that was invented by some idiot.
  7. Dec 6, 2008 #6
    I agree, it further adds to my point. I think that if you're going to use this useless system, use it for looks. Try to find some iridescent stuff, and some l.e.d's instead - maybe green to give off a nuclear, radioactive look - so as to impress your friends.
  8. Dec 6, 2008 #7


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    Water cooling isn't a scam it is actually a better way of cooling a CPU than air. BUT it isn't necessary for a regular PC and is a lot of effort.
    You could regard it like hifi enthusiasts who used to build separate foundation pillars through the floor for their turntables - does it work = yes, can you really hear a difference = no.

    When it comes to running data centres the engineers who plan them have a lot of knowledge of physics, eg. CFD (computation fluid dynamics) modelling of air floor through a server room is now common.
    For high density racks using blade servers liquid cooling is pretty much required - it's hard to blow enough air through a rack that can be generating 10s of KW.

    Liquid cooling is already used in to a lot of smaller desktops and laptops. A heat block on the CPU is connected by fluid filled pipes to a radiator plus fan in a more convenient place at the edge of the case. With higher power CPUs and especially GPUs this might become more common - it's a lot easier to dump heat from the side of PC case than from a small component in the middle.

    ps. The guy who pionered liquid cooling was far from an idiot
  9. Dec 7, 2008 #8
    Water cooling for 'looks' is not a good idea. That is why there are all those horrible 'kits' out there by companies like (can I name them or would that violate forum rules?)
    Water cooling is not 'worthless' or a 'rip off' - however it is not for everyone.
    It is only worth doing if you have problems with heat management - ie. if you have an overclocked system or if you are running multiple gpu's or just one very hot gpu like a 280gtx.
    If you are seriously considering water cooling then you should visit some of the overclocking and modding forums.
    I suggest you get Everest or HWMonitor and look at your systems current temperatures - if you don't know how hot you are currently running then you really can't judge if you need to water cool.
    The simpler solution is to get a good air cooling solution, such as a Noctua cooler. They come with a very quiet and effective fan and are much more effective than a stock cooler.
    Again specific information about prepping aftermarket heat pipe coolers (ie. lapping, washer mods, etc) can be found and debated on the various over clocking / modding forums.
    Just my .02
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