Win 10 Pro
The old PSU stopped working. Changed to Corsair CX650M
How did you reach this conclusion?
That whine may be the PSU itself...that is Corsairs budget line...you may wanna spend a bit more for a better unit.
Unless the sound is obviously coming from the PSU then you at least want prove that the unit wasn't dead on arrival, The safest way to check this is with an ATX testing unit, but another PC will suffice.
Personally I would go with a tester rather than risk another computer, they are not expensive.
Check motherboard for swollen capacitors. Might be around the CPU with tops bloated and crud leaking out of them. They tend to whistle when they vent making a high pitch sound.
Definitely check for this though, if your PSU was the initial problem and a capacitor issue (the high pitch wine) was not present, then it's not outside the realms of possibility that your new PSU has caused the damage.
Or if a (or some) capacitor/s have blown in your motherboard, then it is possible that this caused your old PSU to blow it's internal fuse.
We really need to know all we can about the circumstances of your initial "PSU failure".