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How can I reduce electromagnetically induced noise?

Electromagnetically induced noises are usually harmless

Electromagnetically induced noises, often summarised under the term "coil whine", describe unwanted noises that are generated by an electronic component. The component vibrates when current flows through an electrical conductor or circuit. This can manifest itself as high-frequency whistling, but also as low-frequency crackling or buzzing.

Just about anything connected to a power source can produce some level of vibration. Technically, it is not possible to completely eliminate associated noise. If a device exhibits a clear coil whine, there is therefore in principle still no cause for concern. A system does not lose any performance due to electromagnetically induced noises, nor does it affect the longevity of the product.

Interactions with other devices in the home grid

In some cases, electromagnetically induced noise in laptops or their chargers has been observed to only occur (or to get louder) when other, very specific devices are connected to the same home grid. For example, one customer experienced coil whine only when their electric vehicle was charging in the garage, while another noticed it only when their refrigerator's compressor was running.

The following instructions apply if electromagnetically induced noises occur only when the PC or laptop is connected to the charger or other peripherals.

General advice:

  • Identify the source: Determine which devices are may cause an interference by unplugging them one at a time and checking if the noise persists. This process will help you identify the problematic device(s).
  • Separate devices: If possible, plug the interfering device into different outlets or circuits (phases). This separation can help reduce the interaction between the devices.
  • Check grounding: Ensure that all devices and wall outlets are properly grounded. Improper grounding can lead to interference and other electrical issues.

Advanced advice:

  • It is plausible to consider to use higher-quality power cables and surge protection power strips in order to avoid interference. However, surge protection power strips primarily protect electronic devices from voltage spikes or surges, which could damage the equipment. While some surge protectors may have basic power conditioning features, such as noise filtering, they are generally not designed to address electromagnetically induced noise issues directly. Related article: What can I do to protect my PC or laptop against power surges? (lightning strike)
  • Power conditioners, on the other hand, are specifically designed to filter and stabilize the electrical supply, reducing noise and interference. However, they can also be quite expensive. Since electromagnetically induced noises can have very different causes and do not always depend on the external power supply, there is no guarantee that the use of such additional aids will mitigate the issue.

Possible connection between coil whine and frame rate

Electromagnetically induced noise (coil whine) varies in loudness and frequency depending on the system load. A typical example is that coil whine scales with the refresh rate of the graphics card. This is understandable if you consider that the graphics card goes through different load states for each rendered picture, also called "frame". The load states are: waiting for CPU, accepting commands from CPU (or graphics driver), memory access, rendering frame, outputting frame, etc.

The voltage regulators in the areas between CPU and graphics card are subject to fluctuations during these work steps. If these operations are carried out particularly frequently per second (e.g. 400 times, i.e. with 400 frames per second), then the speed of these voltage fluctuations also increases. The voltage converters have to switch much more frequently, which also increases electroacoustic emissions.

Scenarios with particularly high FPS

400 frames per second (or more) is not an unrealistic figure. Depending on the available computing power and 3D engine, a graphics card always strives for the highest possible frame rate, no matter how high it is. Only very few 3D engines (e.g. of some older console ports) artificially limit their frame rate. Nowadays, this only affects older console ports that are optimised for 30 or 60 FPS (examples: Skyrim; Dark Souls). Engines optimised for PC gaming, on the other hand, sometimes cause enormously high FPS, depending on the game situation and the level of detail of the rendered scene. Even modern console ports usually no longer have locked FPS, because current-gen consoles and TVs are now partly equipped with Adaptive Sync and support 120 Hz or more.

A typical scenario with particularly high frame rates are, for example, option menus in which frame rates of over 1000 FPS are not uncommon in some games. Such high FPS can then lead to clearly audible coil whine effects.

Extreme example: unlimited FPS lead to hardware damage in multiple cases

A briefly famous example of the side effects of particularly high frame rates was the game "New Worlds" from 2021, which had generated such high FPS in option menus that certain graphics cards from a single manufacturer inadvertently suffered abrupt hardware failures due to an interaction between board layout and the extremely frequent voltage changes (source). The game's developer subsequently built a frame limiter into its engine to prevent further damage.

FPS limiter can help against coil whine

An FPS limiter may provide a remedy for coil whine and other possible side effects of particularly high frame rates. For the quietest possible gaming experience (quiet also in the sense of fan noise), it is recommended to set the FPS limiter to a value just below the refresh rate of the screen, e.g. 141 FPS for a 144Hz screen. The NVIDIA control panel allows the user to set a global limit, but also different limits for different games.

However, some games (especially eSports titles at a higher skill level) favour higher FPS rates in their in-game physics (movement, aiming, input lag). For such titles, a higher FPS limiter could be applied, such as 240 or 300 FPS.

The main idea is to set at least some limit (even if that limit itself is very high) so that the graphics card does not "run away" from you in simple scenes (e.g. small interiors or option menus).

Please read the following FAQ article to learn more about why and how to set frame limiters: