I was wondering how loud the apu boards are? I have an apu4 which has a distinct hum to it, which goes up noticably in frequency and volume if a USB drive is plugged in. I'd probably compare it to the volume of, say, a Mac mini running without load and maybe a little louder than an external hard drive; however with the "electric current noise" makes it for me more disruptive.
Is what I'm describing likely normal? I was under the impression the board would be amost silent. I have sensitive hearing, so I might just be triggered by this hum. I'd like to know whether I should be concerned about the hardware's health.