The NZXT Kraken Z63 & X73 AIO Cooler Review: Shiny On Top, Solid Underneathby E. Fylladitakis on August 19, 2020 11:00 AM EST
Although the testing of a cooler appears to be a simple task, that could not be much further from the truth. Proper thermal testing cannot be performed with a cooler mounted on a single chip, for multiple reasons. Some of these reasons include the instability of the thermal load and the inability to fully control and or monitor it, as well as the inaccuracy of the chip-integrated sensors. It is also impossible to compare results taken on different chips, let alone entirely different systems, which is a great problem when testing computer coolers, as the hardware changes every several months. Finally, testing a cooler on a typical system prevents the tester from assessing the most vital characteristic of a cooler, its absolute thermal resistance.
The absolute thermal resistance defines the absolute performance of a heatsink by indicating the temperature rise per unit of power, in our case in degrees Celsius per Watt (°C/W). In layman's terms, if the thermal resistance of a heatsink is known, the user can assess the highest possible temperature rise of a chip over ambient by simply multiplying the maximum thermal design power (TDP) rating of the chip with it. Extracting the absolute thermal resistance of a cooler however is no simple task, as the load has to be perfectly even, steady and variable, as the thermal resistance also varies depending on the magnitude of the thermal load. Therefore, even if it would be possible to assess the thermal resistance of a cooler while it is mounted on a working chip, it would not suffice, as a large change of the thermal load can yield much different results.
Appropriate thermal testing requires the creation of a proper testing station and the use of laboratory-grade equipment. Therefore, we created a thermal testing platform with a fully controllable thermal energy source that may be used to test any kind of cooler, regardless of its design and or compatibility. The thermal cartridge inside the core of our testing station can have its power adjusted between 60 W and 340 W, in 2 W increments (and it never throttles). Furthermore, monitoring and logging of the testing process via software minimizes the possibility of human errors during testing. A multifunction data acquisition module (DAQ) is responsible for the automatic or the manual control of the testing equipment, the acquisition of the ambient and the in-core temperatures via PT100 sensors, the logging of the test results and the mathematical extraction of performance figures.
Finally, as noise measurements are a bit tricky, their measurement is being performed manually. Fans can have significant variations in speed from their rated values, thus their actual speed during the thermal testing is being recorded via a laser tachometer. The fans (and pumps, when applicable) are being powered via an adjustable, fanless desktop DC power supply and noise measurements are being taken 1 meter away from the cooler, in a straight line ahead from its fan engine. At this point we should also note that the Decibel scale is logarithmic, which means that roughly every 3 dB(A) the sound pressure doubles. Therefore, the difference of sound pressure between 30 dB(A) and 60 dB(A) is not "twice as much" but nearly a thousand times greater. The table below should help you cross-reference our test results with real-life situations.
The noise floor of our recording equipment is 30.2-30.4 dB(A), which represents a medium-sized room without any active noise sources. All of our acoustic testing takes place during night hours, minimizing the possibility of external disruptions.
|35-38dB(A)||Very quiet (whisper-slight humming)|
|38-40dB(A)||Quiet (relatively comfortable - humming)|
|40-44dB(A)||Normal (humming noise, above comfortable for a large % of users)|
|44-47dB(A)*||Loud* (strong aerodynamic noise)|
|47-50dB(A)||Very loud (strong whining noise)|
|50-54dB(A)||Extremely loud (painfully distracting for the vast majority of users)|
|>54dB(A)||Intolerable for home/office use, special applications only.|
*noise levels above this are not suggested for daily use
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menorton - Wednesday, August 19, 2020 - linkWhat exactly is the cost of these coolers compared to others listed in the review? Seems common sense to include this, unless I missed the MSRP.
Hyoyeon - Wednesday, August 19, 2020 - linkX53: $130
The Z series is + $100
Cellar Door - Thursday, August 20, 2020 - linkRidiculous prices - for what amounts to a cooler that has a service life of 5-7 years. Its NOT user serviceable and will go in a landfill since most people will just replace it when the pump goes.
My Noctua nh-14D is on a 5th or 6th build and works like new - I have no intention of ever buying another cooler.
Destoya - Thursday, August 20, 2020 - linkE-waste concerns aside, at least NZXT's CLC warranty is category-leading at 6 years. The pump on my X61 died back in March after 5 years of service and they shipped me a new X62 within a couple days of them receiving the support ticket. My other interactions with their support service have been very positive as well, once for replacing a fan that had a bearing go bad and another for getting the AM4 bracket for the cooler.
I don't necessarily like these CLCs having a finite service life but at the end of the day they do perform measurably better than even the best air coolers and that means a quieter, faster PC.
mervincm - Friday, August 21, 2020 - linkIn the exact situation with my Noctua NH-D14. It is also why I just ordered an NH-D15 for a second system. My experience with liquid cooling was that it was more complex/ noise / cost / hassle / e-waste.
godrilla - Friday, August 21, 2020 - linkSet it and forget it Noctua D15 all the way. Even fits in my H210 and a hybrid 2080ti.
Revv233 - Tuesday, September 1, 2020 - linkAny large air cooler can cool just about any chip. I have a 14 & a 15 as well as some phanteks in various builds. Hell I still have a $30 big typhoon kicking around somewhere that im sure would do just fine. At some point AIO's became must have but I don't get it ESP when the noctua still outperforms 90% of them.
shaolin95 - Saturday, March 20, 2021 - linkLol because it doesn't outperform or match about of the recent AIOs
Noctua fans live in denial lol
frbeckenbauer - Saturday, August 22, 2020 - linkbasically, the 120mm version of this is a lot more expensive than other 360mm coolers, you pay for the screen on the pump-block-combo
Guspaz - Wednesday, August 19, 2020 - linkIsn’t this just another rebadged (or rather slightly customized) Asetek cooler?