Weird noise when running Steam?

Question

Hello there.
I woke up this morning and noticed my newfangled Macbook Air (2011 refresh) was making funky noises.
I restarted it several times and noticed it went away.. That is until I logged into every program I run usually. I've boiled it down to Steam, after verifying that it isn't the fan by installing a system monitor and checking the RPM - it doesn't go up from about 2000RPM where it's usually situated. I'd also like to note that the noise doesn't start up until I actually login with my username and it reaches the store frontpage.
Now the noise itself is this weird screeching, shrieking sound similiar to a whistling kettle.. Sort of sounds like a 56K modem only more faint and.. Digital. Could this be some kind of bloated capacitor that only activates when running CPU or graphic intensive applications? Maybe the SSD? I'm pretty stumped and would love to clarify this before I take it in.
Thanks.

Answer 1

Hi PropHat,
There's no moving parts in the SSD so there's nothing that could create friction or generate noise from said friction. So it's one of two things:
CPU/GPU whine
A defective PMU on the logic board that is "overjuicing" the CPU/GPU and causing the excess electrical current to be heard as the noise.
Whatever the case it's not normal or expected behavior. Also I should add that I'm assuming you've turned off the speakers to isolate them in this troubleshooting? Otherwise that'd be the first step, it could very well be them.