Tested this, it kinda works, setting 40 for SoC will make it 1.137V in HWInfo, but will drop to 1.1V under load

But setting 40 for GPU there is no way to check the actual voltage, HWInfo or any other utility will not report the iGPU voltage, not even the X470 has iGPU voltage monitoring in UEFI as far as I see.

iGPU voltage monitoring should be added in UEFI and for the boards that currently dont have SoC voltage  monitoring also.... these 2 things are of utmost importance for any user to be able to check the voltages

I guess it worked setting 40 for iGPU but I cannot verify the actual value :(

Also as far as I know setting lets say 1.1V for SoC and 1.2V for GPU should be possible, or just setting SoC to 1.2 will bump the iGPU to 1.2V also right?

AMD's PDF tells us that the voltages are one way linked, bumping the SoC will bump the GPU to the value of the SoC voltage, but you can bump the iGPU voltage higher than SoC but not lower, does this apply in future or current UEFIs?

Because there is an oddity, what happens when lets say I set SoC voltage to 1.2V for RAM stablity and CPU stablity when overclocking but I also want to overclock the iGPU, I will set 1500MHz and the VID value should not be necessary to set because I already set the SoC voltage to 1.2V and that bumped the iGPU to 1.2V also, how do we let the iGPU voltage at auto in the current implementation?

This applies to all UEFIs.

The other manufacturers have dedicated iGPU overclocking menus in UEFI, and you just set the Speed in MHz and if you want you can change the voltage or leave it on auto.

In AMD/CBS/iGPU OC leaving the VID value to Default of 0 and just setting the frequency and rebooting will boost the iGPU voltage to max I guess and will most likely fry the CPU, this is very dangerous if its the case

Thats why a dedicated iGPU overclock entry should be added in OC Tweaker page, with normal Auto and decimal voltage range.

ASRock AMD CBS SoC Voltage Guide