For a lot of enthusiasts, a full custom watercooling (or liquid cooling, if you prefer) can be essentially the final frontier. Closed loop coolers have been taking off in a big way, bringing watercooling to the masses, but sacrifices are made in the process. The overwhelming majority of closed loop coolers employ aluminum radiators instead of the copper and brass that are used in custom loops, and the pumps tend to be on the weaker side, presumably to both keep noise down and because there's really only one component to cool. I'm still enthusiastic about these products because they can offer excellent cooling performance without placing the undue strain on the motherboard that a heavy tower air cooler can, and they're typically a win for system integrators who don't want to risk shipping damage. Whether you like it or not, this is the direction the market is heading, although pure air cooling most definitely still has its place.

So why look at watercooling? First, establish how important noise is to you. Watercooling systems (and this includes CLCs) occupy an interesting middle ground. For pure thermal-to-noise efficiency, they're basically unbeatable, but if you want absolute or near absolute silence, you actually have to go back to conventional air cooling. The reason is that watercooling necessitates using a water pump, and while they can be tuned down for efficiency, they're never going to be dead silent. An air cooler will always be a fan plus heatsink; watercooling adds a pump.

Watercooling is so efficient because it effectively allows you to spread your system's heat load across a tremendously greater surface area. Water transfers heat exceptionally well, and radiators in turn will be massive, densely packed arrays of copper fins. By being able to spread that heat across one or multiple radiators, you also allow yourself to use multiple fans at low speeds. Alternatively, you substantially increase your system's heat capacity, so if you're looking to overclock a little more aggressively, watercooling may be the way to go.

In my opinion, one of the biggest reasons to go for it is actually the potential for watercooling graphics cards, especially in a multi-GPU setup. While the stock blower cooler for the NVIDIA GeForce GTX 780 is actually a work of art and does a stellar job of keeping that card cool, it simply can't hold a candle to a full-card waterblock that can absorb the heat from every heat-generating component on the card, especially the power circuitry. Suddenly you're not risking tripping the 780's boost clock thermal limits anymore, and the blower coolers aren't generating any more of a racket for your trouble.

Of course, building a custom loop is insanely daunting. This is the first time I've ever built one and while guides exist all over the internet, they all feel a bit incomplete in one aspect or another. There's also the fear of spraying coolant all over the inside of your case, or accidentally frying graphics cards when you install the waterblock, etc. It's also a decent amount of work, and it's not cheap. Truthfully, if I hadn't been able to put this together for AnandTech, I don't know that I'd have ever made the attempt. But the opportunity did present itself and now I can at least share the results with you.

The Components, Part 1
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  • pws328 - Monday, September 30, 2013 - link

    I think this is a great article, with a ton of helpful info. My only real question is why you setup your loop the way you did, chaining all of the components and the radiators together. I would think to get the best cooling possible you would use the following:

    *Pump
    Motherboard voltage circuitry.
    CPU waterblock (Apogee HD).
    *Top radiator (240mm).
    First GeForce GTX 780 (KOMODO-NV).
    Second GeForce GTX 780 (KOMODO-NV).
    Front radiator (360mm).
    Back to pump

    Since you have two radiators why not split up the load, or even run them separately? Is there an advantage to chaining the two radiators together? Again I have no experience with this, just a guess at what I would think would be the most efficient.
  • nitemareglitch - Monday, September 30, 2013 - link

    I think if you had separated your GPU and CPU loops or added a rad you would have made out better. Also, DangerDen would have rocked your socks off.
  • spidey81 - Monday, September 30, 2013 - link

    DangerDen went out of business earlier this year :( Was a sad day when I heard that.

    Separating the GPUs and CPU into separate loops would help, but it wouldn't be very beneficial unless you went with larger rads as well. Which would help with the single loop too. Also, setting up fans in a pull configuration, instead of push, increases the efficiency of weaker fans.

    Essentially, you want the largest surface area of heat dissipation as your case can afford to get the most out of liquid cooling. For example, if you can't fit a long radiator but a thick one will fit, use the thickest one you can afford to get.

    Another thing that wasn't addressed that I saw (but has been touched on in the comments) is loop order. Strictly speaking, it may help with temps out of the gate to evenly distribute the radiators between the loads. However, the longer the components are under a certain set of conditions (i.e. load or idle) the more the temperature in the loop evens out. Thus negating the perceived benefit of placing rads between heat generating components.

    I saw someone state that to achieve the best temps you need to set all your rads to intake air. This may be true, but you'll sacrifice case airflow efficiency. Keep in mind that you won't be watercooling every component in the case. Having balanced flow will not only help cool parts of the motherboard, GPU, and drives but you'll also have less dust buildup to clean out. Not to mention that you may gain up to a degree or two with the fans intaking air.

    Also, the thing with watercooling is that it not helps with cooling, but it looks amazing! Oh did I also mention that it's addicting... :)

    I currently have two systems under water. One is a 2700k with dual HD 6950's in a switch 810 with a 600mm worth of 60mm thick rads. The other is a m-itx build with 360mm worth of 35mm thick rads cooling a 3570k (delidded) and HD 7950.
  • geniekid - Monday, September 30, 2013 - link

    Dustin nailed it when he said watercooling shines in GPU cooling - with good case airflow and a decently sized heatsink you can almost passively cool CPUs these days.

    Unfortunately, there aren't many CLC solutions for graphic cards and the ones that do exist (e.g. HydroCoppers) command a high premium compared to a DIY solution which is already pretty expensive.
  • SkyBill40 - Monday, September 30, 2013 - link

    Very well written and informative. I can understand and appreciate the feeling of satisfaction and/or accomplishment when building something like this. You do make a good point in that "...watercooling may just not give up the performance you were hoping for." This seems to be one of those particular instances seeing as the differences between the OC air and water are not as high as one might expect and certainly don't make the extra expenditure of funds appear all that worth it. Personally, I'm leery of water cooling seeing how water and electronics never mix well. Pre-sealed systems are significantly safer, but your're limited specifically to CPU cooling if going that route. Perhaps a hybrid water/air system might work best for most budgets end produce similar results with far less fuss. But, if money isn't really much of an object and you're a tinkerer, go for it.
  • JDG1980 - Monday, September 30, 2013 - link

    This was supposed to be an article about water cooling, but what you really demonstrated was that Haswell sucks on the desktop (at least the LGA1155 version with a badly attached heat spreader). I think that IVB-E (maybe the 4930K) would have shown off water cooling's strengths better.
  • Hrel - Monday, September 30, 2013 - link

    Fantastic article!

    Pretty much just confirms what I already knew though. Liquid cooling is a hobby, not a practical means by which to build a PC today. Air cooling has just gotten too good. You see gains in benchmarks but nothing so substantial as to translate into being noticeable in real world usage scenarios.

    On top of the insane amount of work, and expense, you have added noise. CPU's and GPU's have built in overclocking today. So any real world gains are nothing but a pipe dream. 11% faster? You won't even notice that, it certainly won't be the difference between playable and not playable. On top of that with a $20 aftermarket CPU cooler you can get your PC totally silent. Don't have to suffer through all the noise of a pump and multiple, air restricted, fans. But even if you're deaf, or live in a way that you soon will be, the performance benefits of a .5%-2% increase in performance translates into literally nothing for real world usage.

    It's a neat idea, cooling a PC the same way we came to cool internal combustion engines. It even had a pay off for a short period of time in computing history. But the idea that anyone's going to get real world benefit from this hobby has reached the point of absurdity.

    Farewell liquid PC cooling.
  • Shinobi_III - Monday, September 30, 2013 - link

    If you get MORE noise with water, you are clearly doing something wrong.

    And really, if you're going the DIY route, get a real pump, the thing in this article is a toy. Barely.

    The all in one kits are excellent for the money. But for true DIY you need real parts. Not this.
  • BrightCandle - Monday, September 30, 2013 - link



    This review unfortunately is total rubbish, there are so many inaccuracies its actually worrying.I'll start with the biggest problem which is the amount of cooling you chose.

    A 120mm worth of cooling with this radiator, that is silent (800rpm) is about 115 Watts. So in total you put just 575 Watts of cooling into your loop at a water temperature of 10C above ambient. With the fans on full its going to be a bit more than around 800 watts of cooling. The components you are trying to cool:

    4770K - 150W
    2x 780 overclocked fully - about 400W each = 800W

    Grand total of 950W.

    So the loop is underspecced in terms of cooling, quite dramatically. There simply isn't enough radiators there even when the fans are running on full power. Further to that its no wonder that when the fans are turned right down the temperature shoots so far up, because the water temperature is DANGEROUSLY high, its actually going to be high enough to be damaging the tubing on full load.

    Realistically to cool a loop like this you need decent radiators (about 130W cooling at 10C delta) and around 8 slots worth of it, ie 2x360 + a 240 with fans designed for low speed fans (high fin density) such as the gentle Typhoon's in an actual watercooling case where those radiators and fans will fit, not this air cooling case that just about fits some thin radiators.

    The second major mistake is that you are cooling a 4770k. These chips are not really thermally limited. The thermal material under the heat spreader sure helps to make them hoter than they are meant to be but delidding them and replacing it and reducing the problem can net 20C but not really any extra overclocking. 22nm simply doesn't overclock as well and 4.4 is about where this chips normally top out. But additionally the 4770K doesn't pull much power even when overclocked, so its questionable if water cooling would ever help, because its only worth it if you chip will pull greater than about 200W, below that air does a better job. Realistically custom water is only worth it for overclocking on SB-E/IB-E and other high power chips, the low power mainstream ones we see today just don't net much benefit especially considering the thermal issues the chips themselves have out of the factory from Intel.

    So realistically you have underspeced the loop making all the components hotter than they should be due presumably to some bad advice and are cooling a processor with water that doesn't benefit from it. If that was it for errors I would stop here but it isn't. I have to say something about the inaccurate statements made in the review as well because they are going to seriously mislead.

    "The overwhelming majority of closed loop coolers employ aluminum radiators instead of the copper and brass that are used in custom loops, and the pumps tend to be on the weaker side, presumably to both keep noise down and because there's really only one component to cool"

    They use aluminium because its cheaper. The pumps are weaker because the loop is shorter and you don't need more, but most pumps aren't noisy at all, they are very nearly silent when a loop is setup correctly. Actually the all in one coolers tend to have noiser pumps because they are attached to something hard - the motherboard. With a separate pump you can mount it on some foam and eliminate all the vibration and noise for $5.

    "For pure thermal-to-noise efficiency, they're basically unbeatable, but if you want absolute or near absolute silence, you actually have to go back to conventional air cooling. The reason is that watercooling necessitates using a water pump, and while they can be tuned down for efficiency, they're never going to be dead silent. An air cooler will always be a fan plus heatsink; watercooling adds a pump."

    Near silence on a high end kit can be achieved with watercooling if you actually spec the loop correctly, which in this case you didn't. The reality is that if you don't have enough cooling and you don't mount the pump on foam then yes there will produce noise, but that is like saying a normal air cooler doesn't work very well if you don't clip it to the CPU properly, its user error. Water pumps can and are quieter than any fan inside of a PSU, they are quieter than most hard drives.

    "Water transfers heat exceptionally well, and radiators in turn will be massive, densely packed arrays of copper fins."

    Water does not transfer heat well, its actually a very good insulator. But what it does do is take quite a lot of heat to increase its temperature and its better than just air in terms of pulling the heat away from the component. The downside of water is its another material the heat has to go through, you need to pay attention to making sure that the water doesn't get hot by making sure there is enough exchange to the air via the radiators to ensure that doesn't happen, otherwise water performs worse than air.

    "Swiftech's HydrX PM (pre-mixed) coolant. the HydrX PM is actually 90% distilled water"
    "This is very similar to how coolant/anti-freeze works in your car; water carries heat very well, but is also corrosive, so chemicals are introduced into the mixture to counteract that effect."

    This isn't the right choice for coolant. Nowadays everyone in the watercooling world is using distilled water with a silver coil. You don't need anti freeze and anti corrosive because it actually performs worse than basic distilled water. The only reason for having anti corrosive in the loop is because you put a metal in there that corrodes, aluminium is the main offender. No one should be putting aluminium in a loop, even with anticorrosive it will slowly eat away at the metal in the components and realistically its already expensive to setup a loop, no point ruining it over a few years. The anticorrosive is pretty nasty stuff.

    "one with a normal fin density designed for low speed fans (these), and one with a higher fin density designed for high speed fans."

    Actually its the other way around. The high density fins work better with lower speed fans and designed for silent running systems whereas the low fin density is for the higher speed fans. Xtremesystem have plenty of charts showing this exact effect and its largely about the static pressure of fans and impedance to the air.

    "Next to them is one of the five Helix-120 PWM-controlled fans intended to be used with the radiators, and the odd-looking dongle is actually a SATA-powered PWM-splitter."

    I have never seen a professional watercooler review these fans, so chances are they are rubbish. There are plenty of fan choices that are good for radiators but not all fans work well for watercooling. The very best can be about 50% better than the worst unfortunate;y. Since I haven't seen a review of them comparing to other fans on a radiator its a bad choice of component.

    "Swiftech sent along their Apogee HD"

    Would not have been my choice of waterblock, it doesn't exactly perform very well compared to all the other choices. Its pretty dated as a waterblock and has never performed very well comparatively. A HK 3.0 will knock about 5C off the CPU temperature in comparison.
  • scook9 - Monday, September 30, 2013 - link

    Good to see you got some experience in watercooling! There have been decent comments made already so I wont repeat what they all said. I will say that people are ridiculous when spec'ing out radiators for loops (kind of like how most people go crazy high on a PSU compared to what they really need). You have more than enough radiator for this build - my proof point is my HTPC. It is an i7 2700k and 2x GTX 570 all on the same loop cooled by a 30mm thick 240mm radiator without out a worry in the world. Yes they are all stock but it still is a non-trivial amount of power being dissipated and cooled. That all runs like a gem on a 650W PSU by the way without coming close to its limits (verified with a kill-a-watt). Also, loop order is pretty much irrelevant so just build your loop in whatever way is the most convenient from a tubing standpoint. The coolant is moving so fast with a good modern pump that the whole loops coolant temperature will normalize pretty quickly regardless of order. Just keep the coolant from getting saturated with heat and you are fine (and with that much radiator you are).

    The fans are probably the biggest chance for improvement - as mentioned you cannot do better than Gentle Typhoons usually. They are made by the Nidec servo company and distributed by Scythe. An important note on fans though when it comes to noise (or at least the GTs) - do not use them as intakes if they are right against a mesh opening in a case - this is loud! In that instance you are better off having them pull air through the radiator rather than push into it (at least better off from an acoustic stand point - have not tested cooling difference).

    The comments on de-lidding and the lackluster result of CPU cooling is spot on - unless you are directly touching the die there will be more heat than you want that you cannot get rid of. Back in the 130W Nehalem days there were decent improvements from watercooling but now-a-days the sub-100W CPUs don't benefit much over air cooling. I do it for aesthetics and because the benefits for cooling a GPU are absurd so adding the CPU to a loop is pretty trivial. My first loop was cooling an i7 965 and 2x 5870s. The 5870s were sandwiched together and both got up to 93c on the stock coolers - once watercooled they were down to 39c and no matter what I tried could not get them over that.

    My final note is on the actual coolant used. There is a lot of fear about water and it being damaging to electronics - while this is valid and true, pure distilled water is an insulator, it does not conduct electricity at all. In addition to having a better heat capacity it is non conductive, WIN! It is also a lot cheaper than the stuff these companies will try to sell you. Just don't mix aluminum and copper in your loop and don't use any dyes and distilled water and a single drop per liter of killwater (or whatever it is called) is all you need.

    Hope this was helpful!

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