About a month and a half ago I decided to buy new parts for my PC - a new motherboard, processor, video card and sound card. After a short time I started to notice a high pitched whistling noise, ...

You turn on your PC, start up a particularly taxing program, and then—you hear it. A high-pitched sound emanating from somewhere as if your ears are ringing. You're not going crazy, it's coil whine, ...

Got pretty loud coil whine when I plug in my fancy new USB mouse (gaming mouse that I got for work because of ergonomics). Never happened before. Comes from the motherboard, as far as I can tell.