Well, it's kind of a beefy one for sure I'm glad it worked for you... I'll have to source some random caps that I have lying around. Mine is even worse (excluding the rattling noise at boot, maybe it will go away when the fan is tighten to the case), because being it a PoE model it has two fans.Thank you! adding a 330µF cap removed the whining noise.
BTW, is that an 122K? Nice find!