Which combo whines the least? 12 PSUs, 3 graphics cards…

Why a PSU can have an impact

“After replacing the PSU, the video card coils stopped whining”. An extremely common statement and yet it always remains on a subjective level, which is a pity. But that is also why we will now look at things in an exact, numerical way. We do this by testing several graphics cards, where for each, noise levels of VRM coils are monitored with each ATX (3.0) power supply used. So how is it with the “whining”? When is it stronger and when is it weaker?

One tip that often appears in internet discussions on how to solve the louder coil whine in graphics cards is to use a different PSU. For some this may sound like a good idea and something they are willing to experiment with, for others it may sound like something that doesn’t make much sense. We were in the latter camp, or (let me drop the authorial plural) me personally. Rather than speculating about something in a “what could it be” way, it’s better to test things out and then draw some conclusions. For starters, though, let’s indulge in a bit of theory.

Why a PSU can have an impact

First, let’s explain why it makes sense to discuss the dependence of coil (graphics card) whine intensity on a used PSU (ATX). Before that, let’s briefly talk about why the coil makes the noise in the first place. The coil itself is basically a wire wrapped around a metal core. You can’t see it on current components because of the use of shielding (that rectangular box), but it’s exactly like that inside. This coil has a voltage applied to it, which creates vibrations. These, because of the design of the coils as such, are the source of the noise. How this noise will sound depends, besides the electrical properties, also on the degree of vibration damping by glue, stabilization.

If the coils were perfectly coated with it, there would be no vibration, no sound. However, to achieve such a state in practice would be extremely expensive, unprofitable, and that is why coils more or less “whine”. In fact, rather than “whistling”, it is a kind of “whirring”. It is in fact a mix of different frequencies of sound, not one distinctive one (like when you blow a whistle, for example).

Coils are noisier or quieter depending on whether they are “better” or “worse” at hitting resonant frequencies at a given job. When they do hit them, they can be quite noisy.

For a more clear idea, we can probably note that coils have some “natural” resonant frequency that arises at perfectly clean voltages. But this (clean, smoothed voltage) is only a theory, and practice may be such that there is always more or less electrical noise. The latter is defined by a ripple of some amplitude (peak to peak in millivolts) and then a time period, or frequency. And we assume that it is the latter (the electrical noise frequency) that can interfere with and affect the “base frequency” of the coils. Negatively, but also positively. The nature of the electrical noise itself does not say whether the coils will be noisier or quieter due to its presence. Equally “aggressive” noise can lead to both results. It is only a question of whether, in interaction with it, the coils will be closer to or further from the resonant frequencies at which the loudest noise is achieved.

Now, on to why, in theory, none of what we wrote above would carry weight. There could be no dependence of coil whine on the power supply used, as long as there is perfect voltage smoothing at the level of the graphics card VRM ahead of the coils (on the capacitors), or smoothing to a degree that does not affect the coil vibration in any way.

However, such a situation can also be considered as purely theoretical and in practice there will be qualitatively different voltages on the coils, which may have an impact on the noise of the coils. Whether it’s dramatic or merely symbolic (or something in between) will only become clear in tests. One must prepare for these (tests) properly, so as not to end up measuring something different than what one wants. But we will get to that in the text of the next chapter with the testing methodology.

“After replacing the PSU, the video card coils stopped whining”. An extremely common statement and yet it always remains on a subjective level, which is a pity. But that is also why we will now look at things in an exact, numerical way. We do this by testing several graphics cards, where for each, noise levels of VRM coils are monitored with each ATX (3.0) power supply used. So how is it with the “whining”? When is it stronger and when is it weaker?

Testing methodology

The foundation is multiple ATX power supplies. We have twelve different models available, of which we still owe you the “standard” tests. But what you could already see is the temperatures of their 12VHPWR cables.

These are the Asus ROG Strix 850G Aura, BeQuiet! Dark Power 13 (850 W), Cooler Master GX III Gold 850, Corsair RM850x Shift, DeepCool PX1000G, Enermax ERT850 EWT, FSP Hydro G Pro ATX3.0, Gigabyte GP-UD850GM PG5W, Chieftec Polaris 3.0 (PPS-850FC), MSI MPG A850G, Seasonic Vertex GX-850 and the SilverStone DA850R Gold.

To eliminate noise from the electrical grid, we use a Kemot Prosinus-2000 inverter for AC voltage with a pure sinusoidal waveform between the socket and the power supply. This means filtering out interference from other devices that are plugged into the grid. Their contribution to the interference of the power grid can vary, be different for each one, and it is important for our analysis to filter them out. Otherwise, we would not only measure how individual PSUs change the noise level of graphics card coils, but also how interference from the power grid interferes with it. The latter should always be minimal and shouldn’t be too noticeable (the PSUs have primary filtering for that too), but it is still an unwanted external influence that is potentially undesirable for this analysis.

I monitor coil noise on three different graphics cards. To draw conclusions from one would be insufficient, because each has a different approach to VRM, uses different components that may respond differently to voltages with different characteristics. The Sapphire RX 7600 XT Pulse is a representative of the “noisiest” graphics cards. With the same PSU, we recorded the loudest coil noise in the standard tests with this card. In contrast, with the Gigabyte RTX 4090 Gaming OC 24G, the coils were very quiet, even surprisingly so. Therefore, it is interesting to see if such a situation will occur with all PSUs (and if some of them will increase the noise level of its coils). And thirdly, the MSI RTX 4070 Ti Super Ventus 3X – something in between the other two graphics cards. In terms of coil noise, but also in terms of performance.

Game Ready 551.61 drivers are used with GeForce graphics cards (4070 Ti Super and RTX 4090) and Adrenalin 24.2.1 with the Radeon (RX 7600 XT).

We use the same test configuration as in standard graphics card tests. From these, you will also be familiar with noise measurement details. For the purposes of these measurements, however, a few things need to be clarified. The usual conditions with the exact alignment of the noise meter, or microphone to the graphics cards remain the same. And these are also the only elements that are the source of noise. The fan on the CPU cooler is switched off during the tests, and the graphics card fans are stopped for the measurement sequence as well. But that’s only for a moment (during the 15-second noise recordings), so as not to limit performance by overheating. In any case, the output is only the noise from the graphics card coils, all else is filtered out. This includes the noise from the coils of the PSU itself or the “pure sine” inventer (the latter is in another room and its activity is completely filtered out).

We chose the Shadow of the Tomb Raider menu (1080p, graphics profile “High”) as the measurement scene. In it, the load is constant and the coil whine does not change over time. However, in order to always capture the same moment under comparable conditions, I always use the same procedure, which takes 615 seconds.

The first 420 seconds is the “warm up” phase, after which we turn off the fan on the CPU cooler and recording of the coil noise with a noise meter (properly calibrated Reed R8080) takes place for 480–495 seconds. Spectrograms (recorded by the UMIK-1 miniDSP microphone) are then created in a time span of 600–615 seconds. The TrueRTA application averages 100 samples during this interval, so that the output is always a sufficiently steady state value of the noise levels at the individual frequencies. The monitored frequency range is 2–20 kHz. Graphics card noise is also present below this range, but that’s aerodynamic noise and we focus on the coils for the purposes of these tests.

The fans are disconnected for all PSUs so that they do not contribute in any way to the measured sound/noise. The activity of the coils of a given PSU is in there to some extent. To isolate the ATX power supply completely in this respect is practically impossible (unrealistic in common practice…). The power supply must always be in relative proximity (something like very long enough extension cables cannot be used, because with them a very significant voltage drop would occur and in higher loads the power supplies would no longer work). The noise level of ATX PSUs is always marginal, the grill (i.e. the open part) is at the bottom, and they are also already at the lower limit of the range of the parabolic collar, which we use on both the noise meter and the microphone to amplify the recorded sound. This is to achieve the highest resolution with the largest possible differences in measured noise.

“After replacing the PSU, the video card coils stopped whining”. An extremely common statement and yet it always remains on a subjective level, which is a pity. But that is also why we will now look at things in an exact, numerical way. We do this by testing several graphics cards, where for each, noise levels of VRM coils are monitored with each ATX (3.0) power supply used. So how is it with the “whining”? When is it stronger and when is it weaker?

Noise level measured with a noise meter

Relative noise level

“After replacing the PSU, the video card coils stopped whining”. An extremely common statement and yet it always remains on a subjective level, which is a pity. But that is also why we will now look at things in an exact, numerical way. We do this by testing several graphics cards, where for each, noise levels of VRM coils are monitored with each ATX (3.0) power supply used. So how is it with the “whining”? When is it stronger and when is it weaker?

Dominant frequencies…

“After replacing the PSU, the video card coils stopped whining”. An extremely common statement and yet it always remains on a subjective level, which is a pity. But that is also why we will now look at things in an exact, numerical way. We do this by testing several graphics cards, where for each, noise levels of VRM coils are monitored with each ATX (3.0) power supply used. So how is it with the “whining”? When is it stronger and when is it weaker?

… and their noise level

“After replacing the PSU, the video card coils stopped whining”. An extremely common statement and yet it always remains on a subjective level, which is a pity. But that is also why we will now look at things in an exact, numerical way. We do this by testing several graphics cards, where for each, noise levels of VRM coils are monitored with each ATX (3.0) power supply used. So how is it with the “whining”? When is it stronger and when is it weaker?

Tonal peaks and noise levels in aggregate

“After replacing the PSU, the video card coils stopped whining”. An extremely common statement and yet it always remains on a subjective level, which is a pity. But that is also why we will now look at things in an exact, numerical way. We do this by testing several graphics cards, where for each, noise levels of VRM coils are monitored with each ATX (3.0) power supply used. So how is it with the “whining”? When is it stronger and when is it weaker?

Complete sound spectrograms

Sapphire RX 7600 XT Pulse

MSI RTX 4070 Ti Super 16G Ventus 3X

Gigabyte RTX 4090 Gaming OC 24G

“After replacing the PSU, the video card coils stopped whining”. An extremely common statement and yet it always remains on a subjective level, which is a pity. But that is also why we will now look at things in an exact, numerical way. We do this by testing several graphics cards, where for each, noise levels of VRM coils are monitored with each ATX (3.0) power supply used. So how is it with the “whining”? When is it stronger and when is it weaker?

Conclusion

Different PSUs, or different characteristics of their 12-volt rails affect the different sound of graphics card coils. And now very carefully: some may hear the difference, others may not. If you look at the results with noise differences, which take into account all frequencies of sound, the difference between the quietest and the noisiest situation is always quite small.

With the tested sample of 12 PSUs, it’s only 2.1 dBA with the Gigabyte RTX 4090 Gaming OC 24G, with the Sapphire RX 7600 XT Pulse it’s 2,3 dBA and with the MSI RTX 4070 Ti Super Ventus 3X it’s 3,5 dBA. The quietest operation in these measurements is with the FSP Hydro G Pro ATX3.0 (s RX 7600 XT), the Seasonic Vertex GX-850 (s RTX 4070 Ti Super) and the Enermax ERT850 EWT (s RTX 4090). The only power supply that was always in the top five with all the graphics cards is the MSI MPG A850G. After averaging the rankings, it is therefore also the “relatively quietest” or perhaps more accurately the “most balanced”. It was never the quietest in the observed scenarios, but it also didn’t happen that it somehow dropped significantly (towards the noisier ones).

For example, the RT 7600 XT Pulse coils are relatively quietest with the FSP Hydro G Pro ATX3.0, but the RTX 4070 Ti Super Ventus 3X already achieves the third worst/noisiest result from the end with this power supply. The rankings change depending on the graphics card, sometimes dramatically. Each graphics card generates different vibrations on the coils and the resonant frequencies differ significantly.

The only model that is always the noisiest is, unfortunately for Cooler Master, their GX III Gold 850. Yet subjectively, someone may not evaluate it that way. We are still talking about single-digit values measured by a noise meter. For a precise analysis, you need to go to the level of the spectrograms, which tell you which frequencies of sound are noisier and which are quieter.

We have written about the GX III Gold 850 as the noisiest PSU, but there is sure to be someone who, after a subjective judgment, will disagree with this statement. On the grounds that they will be more sensitive to tones of other PSU’s coils. Moreover, these tonal peaks are variable, depending on how the load “pulses” (feel free to substitute the load with the framerate of a game or 3D render in Blender). Scene to scene it’s naturally different, and the ranking of noise level can be different for the same “PSU + graphics card” configurations.

Giving a guaranteed recommendation for a power supply with which the coils of a particular graphics card will always be the quietest is certainly impossible. The calculations here eventually include interference in the power grid (eliminated in our tests by simulating a pure sinusoidal voltage at the socket), which is unique for everyone and may or may not react differently with a selected PSU. It depends on whether the nature of the interference (from the power grid) can manifest itself in the form of higher harmonic frequencies.

There will always be conflicting opinions on the degree of influence of the PSU on graphics card coil whine, for the reasons mentioned above. There are too many variables for things to be clear, and general conclusions about what is “quieter” and “noisier” are simply not possible. By replacing the PSU it is indeed possible to suppress the sound frequency that user A has evaluated as critical, but a different one can pop up. One that bothers user B for a change. And even if the peaks are at the same frequency, they have different noise levels (see also this comprehensive table for an overview of the tonal peaks, along with the noise level they represent).

The sound of graphics card coils spans a very wide spectrum, and it is virtually impossible to silence this across the board just by a different voltage characteristic of a PSU. The way to noiseless operation is to avoid vibrations arising on the coils. However, this would again be expensive to manufacture and simply unprofitable. At least as far as the graphics card segment is concerned.

Are we using “too high quality” PSUs and the situation is significantly worse with cheaper ones? To be continued…

English translation and edit by Jozef Dudáš

• Contents
• Why a PSU can have an impact
• Testing methodology
• Noise level measured with a noise meter
• Dominant frequencies...
• ... and their noise level
• Tonal peaks and noise levels in aggregate (chart)
• Complete sound spectrograms
• Conclusion