Как вы «замалчиваете» не-HDD, не связанные с вентилятором звуки на ноутбуке?

I have a new Dell Inspiron 15 7547 laptop and it makes an annoying high-pitched buzzing sound whenever running on AC power.

This is not HDD noise (there is a separate normal sound when the HDD is working). It is not fan noise (that is also present and it is different/quieter). It is also not coming from the speakers (the noise does not respond to volume control).

The buzzing noise is correlated with CPU usage. Low CPU usage results in a loud noise while high CPU usage results in no noise. For example, continuously scrolling in the browser will shut it up.

I know that electronic components can make noise, and I believe that this is the case. Is there anything I can do to shut it up? The buzzing is just as loud as the HDD’s noise, but it never stops and becomes really annoying.

As the noise is connected to the load (and thus current consumption), this might be a case of a noisy DC-to-DC converter whose switching frequency falls into the audible range.

It is hard to tell whether it is serious or not, but I would definitely look into replacing the laptop if it is still under warranty as a big shift in DC-to-DC switching frequency can quite often have an impact on the voltages it generates.

Even if it is currently working without problems, you might find some of more sensitive components just dropping dead one-by-one over the long-term.

I think I had the same problem a while back. When the CPU is working at full speed, it is silent, but when the workload is lower, the CPU goes into power-saving mode. That is when it started making noise.

My problem was solved by switching off D-States in the BIOS. Amazingly, neither the computer support at our company nor the two engineers DELL sent out to fix the noise could solve my problem. Luckily, I found the answer on the Internet.