Ive noticed this too. However, Ive been able to get around this by using adaptive voltage.
So for my 8700k OC im aiming for 1.3 volts. Setting it manually does nothing like you said.
But setting it to Adaptive mode, 1.30 for turbo mode CPU core voltage, with a negative offset of 1.125 gets me around 1.3 v

Would like to see if someone with more knowledge about this explain why manual isnt working though. It is pretty scary because the normal AI likes to feed the CPU crazy voltages probs to insure stability.
Once I tried bumping my multiplier to 50 and set 1.35 V on manual. CPUZ read the voltage as 1.55+ at some points. I turned off my system right as I saw those numbers to prevent damage. I dont know what the AI is doing but this could really mess up someone's CPU if they dont realize the manual isnt working and the mobo AI is feeding the CPU insane voltages. :mad:

There are also other ways of getting it closer to the set voltage like:

Nate152 wrote:
OK,

Go to Internal CPU Power Management and set:

IA AC Load Line - .01
IA DC Load Line - .01

DIGI+
LLC to level 6

This should put the voltage close to 1.270v which I see you have it set to. Being you'll be at a lower voltage you may not be stable at 1.280v, cross your fingers. 🙂

but I really dont understand why its made to be so difficult.