These hi-pitched noise are usually from coils. I battled then on DFI LP B mobo so badly, that I poured silicone on the coils. But no help. After the mobo capacitor exploded and mobo stoped working I realized, that the Bad Caps (tm) plague is behind this noise. The bad caps lose their characteristic, forcing the regulation chips oscilate wildly, causing this noise.
Replace bad caps and problem will go away like breeze.
In fact, the disabling of the power saving mode on CPU confirm that. The problem is the CPU VRM phase, witch is getting bad by the bad caps. Don't get fooled, tough. There are only like 5 companies that make quality caps (Rubycon, Nichicon, Samxon, Panasonic, some Hitachi big caps models, Elna for audio and that practically it is... some rate Chemicons as good caps, I tendt to disagree) and there are plenty of fakes. Polymers included and yes, they fail too. Why the hell you think they (the polymers) are rated at 2000 hours too? Never trust Elite Taiwan polymers or such "hot shots."
Even respectable manufactores using KNOWN fake caps. Apple too.
Once they use golden letters Nichicon HM caps
(this is, of course, only a joke for capacitor gurus... only one Nichicon caps come with golden leters - HZ ones, the best elyte caps in the world, the Samxon GA are par-to-par with them... so Nichicon HM caps with gold letters are clear fake spoted on first sight, no need to talk later... and sure enough, the bulge and machine whine... till death)
So, whining coils means - beware, I have bad caps inside and I'm about to give up!