Noctua NH-U 12

Author: J. Micah Grunert
Editor: Howard Ha
Publish Date: Tuesday, May 9th, 2006
Originally Published on Neoseeker (
Article Link:
Copyright Neo Era Media, Inc. - please do not redistribute or use for commercial purposes.

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Like any hardcore computer enthusiast, we here at Neoseeker are always on the prowl for the latest in extreme cooling. We were excited, our digital hearts all a flutter, to get our hands on the NH-U 12 CPU cooler from Noctua. All who saw it in person were quite impressed with the sheer presence of this cooler -- it almost rings of some Art Deco center piece resting under white halogen light. It is a Goliath, a monolith, an obelisk unto itself that is absolutely Schwarzenegger-esque in proportions.

The NH-U 12 is an absolute giant that is equipped with a robust cast/machined solid copper base. Clamped and soldered to this base are 4 copper heat pipes, each molded from 1/4" diameter thin walled copper tubing. Wrapped around those copper spires - 38 stamped aluminum cooling fins. This cooler is perfectly industrious in its nature.

Though Noctua might not spring to mind when one thinks of coolers, it is destined to become a PC fanatic's favorite. Noctua itself is a collaborative development between two companies and a research foundation:

These three organizations have come together in unique partnership to help develop the future of computer cooling technology. In forming Noctua, they have set their sights on PC heat dissipation. Rascom is a long standing distributor of high-end PC parts, with a great deal of their focus upon performance parts. Kolink, a Taiwanese manufacturing corporation, has spent years manufacturing fans and cooling devices that are both effective and affordable for the masses. Finally, the Austrian Institute of Heat Transmission and Fan Technology tirelessly researches new and improved methods of heat transfer and dissipation. With this sharing of ideas and methodologies, Noctua is certain to become a name all PC overclockers will know by heart.

Let's strap on the NH-U 12, cook some chips, and see what it can do!

The box is of standard fare for this heat sink, or any heat sink. The packaging is quite attractive, and catches the eye, drawing you in for a closer look. The box is considerably heftier than you would assume at first glance, letting you know that there's good stuff inside. I feel like a kid rifling through a box of kids' cereal trying to find the toy inside.

There are a lot of little bits and pieces bundled with this cooler. The included accessories allow the NH-U 12 to be mounted on any modern AMD/Intel socket -- S478 (older Pentium 4/Celeron), LGA775 (newer Pentium 4/Celeron), and any K8 platform socket (S754, S939, or S940). All of your bases -- or is that sockets? -- are covered.

Also included are all of the little mounting screws you need to bolt this cooler to your rig. Now, these aren't cheap-parts-bin fasteners -- they're definitely of higher quality. I know, sometimes a cigar is just a cigar and sometimes a screw is just a screw, right? Wrong! A well-machined fastener speaks for the entirety of the product and how much focus was put on quality. We also found a very thorough and well-written instruction manual to aid in assembly of the cooler -- in English, Spanish, French, and Austrian, no less.

Unfortunately, but not surprisingly, Noctua did not include a boxed fan with this heatsink. It would have been nice if they'd tossed in a fan or two, but we weren't expecting to see one. High-end coolers back in the day, such as the venerable MCX-462 from Swiftech, did not include fans either. This gave the enthusiast the option of choosing any fan they wanted, rather than being saddled with whatever the manufacturer chose. Thermalright follows this kind of approach for many of their products as well -- concentrating on the heatsink is the #1 priority for these companies.

Last but not least, we also found two pairs of anti-vibration pads in the accessory kit. These small strips of silicone stick onto the fans or onto the cooler itself, and help to reduce noise caused by the vibrations of the operating fans -- a nice little extra to take the buzz out of your box.

Finally, we have the cooler itself. Let's take a closer look at this beast, shall we?

We did a test-fitting of the NH-U 12 in three different enclosures. The first was the Thermaltake Eureka Aluminum Case Home Server. This thing is massive and the NH-U 12 had more than enough room to breath. There was probably enough room left for a cat or two to take up residence inside.

The next case we dropped this cooler into was the CoolerMaster Centurion 534. Now, this case has a shroud for the CPU fan in the side panel. Unfortunately, this shroud got in the way of our NH-U 12, and the only way to properly use the NH-U 12 in this case was to remove the shroud. A pity, for all of that cool air would have fed the cooler nicely.

Finally, the last case we test-fitted the NH-U 12 in was the AeroCool ExtremeEngine 3T Twin Turbine. Once the side panel was put back in place, there was only 2-3 mm of clearance between the massive turbine on the side panel and the top of the fans installed on the NH-U 12. There was literally no room to spare.

If you are interested in this cooler and you have a mid-tower case, choose carefully. The NH-U 12 should fit in almost every regular mid-tower and full-tower case on the market today. Cases with any additional fancy doodads might be more problematic. Before purchasing the NH-U 12, make certain that your vendor or retailer has a return policy, in case your chassis isn't deep enough. Noctua has a cooler of identical design, but smaller stature, dubbed the "NH-U 9". The NH-U 9 is the answer for those close-quarters enclosures -- it will fit any 92x92x25 mm and 80x80x25 mm case fans. Barring some creative cutting with a hacksaw, the NH-U 9 -- while being smaller -- is still relatively hefty, and would not fit in your favourite SFF enclosure. These heatsinks are purely for those of us with roomy cases.

As it is plain to see, the is a hulk of a cooler that makes other PC parts look quite diminutive.

And now, without much further adieu, the NH-U 12 from Noctua in detail ...

The most important part of any cooler is the mating base. Almost any metal will do the job, but copper stands supreme as the thermal transfer medium of choice, and the Noctua NH-U 12 uses a base of solid-cast copper. It is well-machined with excellent tolerances and attention to detail, and it (along with the heat pipes) also boast a polished finish which ought to help dissipation of heat due to that fact alone -- at least in theory. It can also be seen that the base has fine concentric rings from surface grinding. Not only does surface grinding provide a surface flat to within .0005", but those rings help to trap a bit of thermal compound and increase the surface area of the mounting face.

During a quick visual inspection, it appears that the base of the NH-U 12 is of pure copper, and not alloyed at all. Some cooler manufacturers will use copper alloyed with a bit of nickel and or tin. This makes the metal cheaper, but also reduces the thermal capabilities of the base. Unfortunately, aside from having some experience with metal working, or having a laboratory, there is no simple method for determining if a copper sample is 100% pure or not. Regardless, I trust that Noctua has used pure copper in this base.

While well-engineered, I am going to be picky and mention one grip that I have with the base. Take a look at the following picture:

Those scars on the side of the base are casting flaws. The base of the NH-U 12 is obviously cast hot, and then machined and polished smooth. Little casting imperfections like these won't affect cooling performance greatly, but casting has other shortcomings. When casting molten metal, the mixture is never completely homogeneous, meaning that more often than not, there will be inconsistencies in the cast product. One part of the product might be of higher density than another part, or vice-versa, and this can affect thermal heat transfer greatly. What would have been preferred is a base machined from an extruded bar or billet block of copper. An extruded bar is red hot metal that is forced through a die, not unlike meat through a meat grinder. It is then pressed between rollers to the desired specifications and measurements. A billet block is just metal that is cast under pressure. It's then machined into one large square or whatever desired size. These methods help to produce a far better metal product with fewer flaws.

As you can see, the Noctua NH-12 U's heat pipes are mated to these concave valleys milled into the copper block. They are then soldered and clamped into place. This works great, helping to suck away all of the heat. Now, I may just be splitting hairs here, but I would have liked to see the heat pipes flattened on one side and then soldered into a flat valley in the cooler base -- at least this was my initial wish. After contacting Noctua, we learned the they had experimented with this method. In flattening the heat pipes to build an ellipse, a reduction in thermal performance was discovered. Noctua said that a flattened heat pipe showed upwards of a 20% reduction in thermal conductivity. I would have thought that more flat surface area equals better heat transfer, but sometimes educated hypothesizing doesn't end up to be correct. Whether it be change in coolant flow or augmentation in thermal dynamics, the engineers at Noctua figured it out, and apparently the concave valley simply works better.

The heat pipes themselves are of a 1/4" thin walled copper tubing. They are bent with the most elegant curve and run the length of some 33 cm or 13 inches. They're crimped over on the top ends, but I would have preferred to see 1/4" flat end caps instead. The four heat pipes are wrapped in aluminum fins that measure only .5 mm thick. These thin fins help to dissipate all of the unwanted heat rapidly.

If you're not familiar with how a heat pipe works, the concept is really quite simple. Heat pipes contain a small amount of isopropyl alcohol -- the same you would buy at your local drug store. Other liquids can be used, including water, but something with with a low evaporation/boiling point works best. In the case of isopropyl, it will start to evaporate quickly at about 35 degrees Celsius. At 89 degrees Celsius, it will start to boil. In a heat pipe, the alcohol that is being heated by the processor will evaporate. As it travels up the pipe, it is cooled and it's temperature will fall. Eventually, the alcohol vapour will condense at the top of the heat pipe and trickle back down towards the heated cooler base. The cycle then repeats itself. This cycle of evaporation and condensation is what helps to cool everything down. It is, in essence, a cheap phase-change system.

Well, there's everyone's science lesson for today. Let's get to the installation!

Installing the Noctua NH-U 12 cooler is painfully straight-forward, though a second pair of hands could be of help to some. In our case, we tested this cooler with an Intel LGA775 platform (specs on next page!). We attached the 'X'-shaped retention bracket to the rear of the motherboard, along with the stand-off brackets to hold things in place. We made sure to use the included fiber washers on the top of the motherboard, as we don't want to scratch or short out any traces.

Above are the two "stand-off" brackets for LGA775. The brackets serve the purpose of keeping the retention bracket in place, as well as providing an interface for the mounting of the actual cooler.

One important thing to note is that with these stand-off brackets in place, the processor can't installed or removed. The CPU must be installed before you install the Noctua -- and to take that further, you will have to take your motherboard out of its case in order to do a CPU swap if you have the stand-offs in place.

Next, we lay down a bit of Arctic Silver and attach the cooler (note that the photos above depict the stand-off brackets installed alongside an empty socket). This is where those extra hands might come in handy. The screw-down springs that keep the NH-U 12 in place help to exert sufficient pressure against the top of the processor, allowing for proper thermal transference. An individual can attach the cooler by themselves, but asking a friend to hold the cooler down would save in a little bit of frustration.

Now we have to clip on the fans. Noctua was kind enough to supply us with a pair of Coolink 120 mm fans. They proved to be whisper quiet (as you'll see shortly) and quite attractive. There is nothing in the NH-U 12 manual that explicitly mentions dual fans, but in order to satisfy our own curiosity, all of our testing was done both with one fan blowing on the NH-U 12, and two fans moving air in the same direction (one blowing on to, the other sucking from).

Let's take them out of the box ...

The Coolink fans come with a host of included hardware. The screws we don't need, but the speed dials and the PCI-slot brackets for the speed controls we want. The specs for these Coolink SWiF-1201 fans look as follows:

  • Rotational Speed: 700-1200 RPM
  • Airflow(m3/h): 40-65
  • Acoustical Noise (dB/A): 9-17
  • Input Power (W): 0.84
  • Input Current (A): 0.07
  • Voltage Range (V): 6-13
  • It's time to clip the fans to the NH-U 12. The first thing we want to do is use the anti-vibration pads included with the NH-U 12. These strips have an adhesive backing and just attach to the face of the fans.

    Next, we use the wire retention clips provided to secure the fans. This is a very simple process in practice, though it may sound somewhat complicated when written. The flat length of wire hooks around a notch on the heat sink. The angled ends of the wire clips rest in the fan's mounting holes. It's a quick and simple design that works well. It also reduces weight. Using heavy screws would be undesirable.

    As you can see, this is a relatively pain-free method of installation. Quick to install, quick to remove -- I like it.

    Test Setup

    The Noctua NH-U 12, along with the competition, was tested on the following platform:

    And the software we employed was the following:


    The first thing we did was to measure the ambient room temperature. Our highly-scientific $5 thermometer read 24.5C throughout all testing. We tested a total of five coolers, and the four that will be compared to the NH-U 12 are:

    Our testing methodology was to clean both the CPU and cooler mounting surface as well as possible with rubbing alcohol, apply a fresh drop of Arctic Silver 3, install the cooler, and boot the system up with the fan speed on high (in the case of those coolers with adjustable fans). We waited approximately five minutes for Windows to settle down, and for the cooler and processor to come to equilibrium. We then took an idle temperature reading.

    After that, we would fire up two instances of CPU Burn-in v1.01 with error checking disabled, and run those while keeping an eye on ASUS' PC-Probe. We would continue monitoring until the CPU temperature would not go any higher, and sometimes start drifting between two numbers in an up-down fashion. This was our load temperature. We would then shut down CPU Burn-in, and allow the cooler to dissipate its heat quickly while the fans were still on high. Again this was done until the temperature appeared not to drop any lower. The fan speed was then set to low, the cooler was allowed to reach equilibrium again, and the process was restarted.

    And now, the results. First up are idle temperatures:

    The Noctua NH-U 12 performs exceptionally here. The G-Power is a tough competitor to beat, but the NH-U 12 manages to do just that -- and by a sizable 4 degree margin at the low fan speed with one fan. A second fan got us a further 1 degree decrease. High fan speeds show us that the NH-U 12 with a single fan is identical to the G-Power in terms of cooling performance. Both water coolers have a clear advantage here, while the stock Intel cooler just doesn't stack up at all.

    Let's see what happens when we crank things up a few notches:

    Well, everything got hotter, but the places didn't change at all. As you can see, the Noctua was nudged aside only by our two water coolers, but not by much at all! For an air cooler, this is nothing short of astounding. The monolithic NH-U 12 completely butchered the G-Power, a cooler that has become our overclocking chiller of choice. Obviously, the stock Intel cooler can be melted down and made into something more useful -- like a stylish paperweight, for instance. I have no doubts in my mind that the Noctua NH-U 12 will become a lab favourite from now on. This graph warrants another look, as the NH-U 12 is outdone by higher-end water coolers by a mere 1-2 degrees. Air is making a comeback.

    Noise Levels

    Noise levels are one of those things that not too many people tend to think about when buying a cooler. When they get it home, what you thought to be a whisper at the store turns out to be a roar in your recreation room. All of the coolers tested have some measurable noise levels, and some of the figures may surprise you.

    Our testing methodology here was quite simple. For the close-range measurement, we pointed the microphone of our Omega HHSL-1 decibel meter at the fan of the cooler, approximately 17 cm (5 inches) away, and away from the airflow so as not to introduce "false" noise. The far-range test was done in the same fashion, though approximately one meter away.

    Remember, lower is better!

    To be fair, the Noctua NH-U 12 doesn't actually create any noise itself -- the fans do. Since the fans are consumer-supplied, take these figures lightly, unless you purchase the same Coolink SWiF-1201 fans that we used.

    Alright, so it's clear that the NH-U 12 beats every cooler we pitted it against, and by huge margins -- even with both fans. Some of the figures were within a hair-width of each other, especially when it comes to the 3D Galaxy and G-Power at low fan speeds. The results really do speak for themselves -- once you stick a Noctua NH-U 12 with a Coolink fan or two inside your case, you'll never hear them again.

    A lot of this peace and quiet can be attributed to the fans, as I already mentioned, but a great deal is thanks to the sleek shape and design of the NH-U 12. Because of the flat aluminum fins it uses, there is practically no air turbulence produced. Turbulence can create a lot of noise and amplify the drone of a fan. Concurrently, with there being little turbulence in the fin design, the air being passed through can absorb heat far better.

    Something that was discovered, and quite by accident mind you, was that there might be some clearance issues with oversized motherboard chipset heat sinks. Our ASUS P5WD2-E makes use of a rather tall, passive heat sink design, and we found that the NH-U 12's lowest fin was right up against this heat sink. This is definitely something to include in your decision process for any over-sized cooler purchase.

    I'm going to save my words and your time, and just say this: The Noctua NH-U 12 is by far the best air cooler that we have ever tested, and with the right fans, it is the quietest active cooler that we have tested as well. The cooling performance of the NH-U 12 approaches water-cooling levels, and it gives those expensive, ready-to-install water coolers a run for their money.

    However, let's back up a bit, and think about what is important in any cooler. It really comes down to four things:

    Everyone gets a cooler when they buy a processor, and the stock coolers from Intel and AMD do a splendid job, but they're not enthusiast-level products. They, like all coolers, have a certain thermal transfer capacity. Every copper-based, aluminum-finned cooler will cool the same, up until a certain temperature. Once that temperature is exceeded, then it's time to start looking at better cooling options. Based on sheer size and surface area alone, it should be obvious that the Noctua NH-U 12 has better thermal capacity and dissipation than most other coolers. A picture speaks a thousand words.

    Whether your machine is aggressively overclocked and your current cooler isn't cutting it, or you're just a power-user who wants to make things a little easier on the ears, the NH-U 12 is a solution for both camps. It will allow you to take full potential of whatever extra clock speed margins are lingering around, but at the same time, your ears won't even know it's there.

    There is a weight dragging the NH-U 12 behind, and that is the issue of size. With any cooler of oversized proportions, there is never any guarantee that it will fit flawlessly in your current system. All it takes is a capacitor or over-hanging support in your case, and it's either no-go for that cooler, or you're off to the store to purchase yet another component. We can't stress the importance of doing some measurements and eye-balling the clearance in your current system before you buy something as massive as the NH-U 12.

    All in all, the NH-U 12 is an exceptional product. With a price of about $50 USD, it is at the high-end of the spectrum for air coolers, but at the same time it shines above the best air cooler that we had in the lab up until this point, which had an MSRP equal to that of the NH-U 12. We dare say that the NH-U 12 might be one of the top, if not THE top air cooler on the market.

    The NH-U 12's design is utilitarian and industrial in nature, giving that sleeper PC an aggressive new look, but without the added roar of some of those other whiz-bang add-ons out there. The engineering is impressive, bearing the marking of something completely unusual and out-of-this-world. Coolers in the past have either cooled extremely well, but sounded like a howling storm, or been whisper-quiet but cooled only the lower extremities of "acceptable". The NH-U 12 from Noctua is both the quietest air cooler we have had the pleasure of using, and also the best-performing air cooler we have had the pleasure of using.

    Noctua ought to be congratulated on a job well done. It is very rare that a new-comer can show up on the scene like this and wipe the floor with the competition. The price may turn some away, especially since a fan is still required, but no one ever said that top-notch performance came at a bargain-basement price. This one is a keeper.


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