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 only manually. Fans can have significant variations in speed from their rated values, thus their actual speed during the thermal testing is being acquired 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

The AMD Coolers Testing Results, Maximum Fan Speed (12 Volts)
POST A COMMENT

82 Comments

View All Comments

  • SetiroN - Friday, July 22, 2016 - link

    Such a useful comparison!
    Let's see which other stock cooler that you will never get to replace your own stock cooler would be better.

    /s
    Reply
  • SetiroN - Friday, July 22, 2016 - link

    I mean seriously, the massive marketing campaign AMD has been doing for this wraith cooler is the epitome of their lack of R&D investments. Makes me so stupidly sad. Reply
  • JoeyJoJo123 - Friday, July 22, 2016 - link

    Makes you stupidly sad that they bundle the best stock cpu cooler out of any released ever? Why?

    It's a cooler that I wouldn't be shamed to choose not to get an aftermarket HSF for, as it's basically just as good as one, and it's one of the only things they can do to get people interested in their CPUs, as they know and you know and I know that their CPUs would be lackluster until Zen potentially comes out with potentially competitive value against Intel CPUs. In other words, they know they're stuck shipping slow CPUs right now, but the least they know they can do is bundle in a pretty neat stock cooler, and that might be enough to sway some buyers in their favor, which isn't a terrible thing, as AMD's already struggling to stay afloat.
    Reply
  • SetiroN - Friday, July 22, 2016 - link

    How much energy they have to put into marketing their stock cooler makes me sad, yes, because at this point it's the best part of the bundle.

    When a once great CPU manufacturer has to tell their customers that their CPU is better because... it has a better cooler, I think of the moment I first saw a K7 and tear up a little.
    Reply
  • looncraz - Friday, July 22, 2016 - link

    AMD hasn't put a lot of energy in at all, they made the cooler, they made a quick video, uploaded it, and everyone else did most of the work. Beyond that, they just list it as a value-add - and it is a very good value-add, indeed. Reply
  • close - Monday, July 25, 2016 - link

    Ignore him. He's a troll and not even a very good one. I bet he was hoping for some kind of support. He'll keep repeating the same "the best thing a CPU manufacturer's got going is their bundled cooler" because he somehow thinks that backing out from this stupid statement will make him look even dumber in other people's eyes than keeping it up. Reply
  • nathanddrews - Friday, July 22, 2016 - link

    Eh? The AMD Wraith is clearly a kickass stock cooler. I, for one, welcome the opportunity to not need to buy additional bulky HSFs. I've got 212s on most of my PCs. It's nice to know that I don't need to for an FX build. Reply
  • AS118 - Saturday, July 23, 2016 - link

    I agree. I can't say this enough, the Wraith is pretty much a 212 in terms of performance yet it is SO easy to install. Don't even have to put on a custom backplate. I really hope Zen CPU's have the Wraith or something similar.

    I'd never have to buy another 212 again if AMD keeps making these. (As long as I was buying an AMD CPU that had one)
    Reply
  • Samus - Sunday, July 24, 2016 - link

    Personally I like the direction Intel went in, by not including a cooler at all and reducing the price of the CPU accordingly ($10-$20 vs Haswell) Reply
  • TheinsanegamerN - Wednesday, July 27, 2016 - link

    the 6700k is $10 more then a devil's canyon 4790k. The price went UP, not down. Reply

Log in

Don't have an account? Sign up now