Testing Methodology

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.

<35dB(A) Virtually inaudible
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

Introduction & the Cooler Testing Results
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  • PeachNCream - Saturday, February 10, 2024 - link

    Using possibly charged terms to brand a product demonstrates a lack of research on the part of the company. EK, for years, named their water coolers "Supremacy" and the Europeans behind it failed to note the problematic ties that has to racism in the United States. They only recently rebranded, if I'm not mistaken (honestly its too deep into the PC industry for me to be bothered using a search engine to find out), but it is sometimes difficult for the Chinese to understand the cultural implications of brand choices just as much as western companies have oft caused brand errors by attempting to incorporate Asian themes in their own products.
  • TheinsanegamerN - Wednesday, February 14, 2024 - link

    The term "offensive" is offensive. Why are you so intolerant of the millions who have died in offensive military campaigns throughout human history?
  • GhostOfAnand - Thursday, February 15, 2024 - link

    Yes, words don't denote anything, and terms don't connote anything. Congratulations on your *big* discovery. /s

    P.S. I have no interest to continue. Please reflect on what aspect of my initial comment triggered you and what that says about how you perceive the world and engage with those around you.

    For example, the former Czech Republic is now referred to Czechia in English, as is their wish. It sounds weird to me, but I respect them and so be it. Turkey is now Türkiye in English. Côte d'Ivoire is what the British used to call Ivory Coast, but their colonial French name is how they wish to be referred to in English. More recently India wants to be referred as Bharat in English from the Sanskrit.

    All this is just a small slice of human language, its interaction with human culture, and human psychology.
  • SanX - Friday, February 9, 2024 - link

    Any good suggestions for the watercooler capable to withstand combined power 800-1500watts of future Turin SP5 socket processors and next generation videocards? Where are old convection cooling desighns without fans which turn our computers into wind turbins or bitcoin mining factories.
  • meacupla - Friday, February 9, 2024 - link

    Yeah, go full custom, and have at least 2x360 or 2x280 radiators, and use noctua sterrox fans.
  • SanX - Saturday, February 10, 2024 - link

    I think you are right if you are confident with your custom design but Linus Tech guy kind of discouraged me from doing that despite of his unlimited budget with that. He made one for Genoa and failed miserably as his cooler leaked water. I will try SilverStone XE360-SP5 cooler which looks very weak and if it will also fail to cool below 52C like fail all air coolers with such power constraints i will be forced to invent the bicycle myself. Thanks for pointing on Noctua sterrox fans
  • SanX - Sunday, February 11, 2024 - link

    52C is throttling temperature. Yes, as low as this. Any reference on good high power custom designs and the source of reliable parts for it?
  • meacupla - Sunday, February 11, 2024 - link

    You should go ask somewhere like Level1tech forums, where there is a larger base of EPYC users.
  • back2future - Monday, February 12, 2024 - link

    [ just got aware of that most reviews for/with novelty hardware is about initial conditions review, but rare later reviews on long term durability or altered parameters (or e.g. MTBF/MTTF (MTTR or MTTA are less meaningful with this type of technical devices) verification) (?) ]
  • TheinsanegamerN - Wednesday, February 14, 2024 - link

    Linus also has lost two entire data racks and major backups because he doesn't know how modern server storage arrays work.

    In case its not spelled out, he's a bit of a derp. Take what LTT does with a morton factory of salt.

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