This probably isn't a supported topic here on Asus forums but here goes. For fun I had modded a Z270 Apex IX to run a 9700K cpu using a ported bios from an Apex X. Anyhow afterwards all seemed well for a while but noticed that when set to adaptive mode the cpu voltages weren't following the VID tables correctly or boosted up enough to be stable long term. For example if everything was set to Auto would get a starting voltage of 0.889 or something low. After tweaking and setting 'adaptive additional turbo voltage' to like 1.28 that worked while cpu was in turbo multiplier ranges but otherwise the volts for lower frequencies seemed low.
This resulted with random endless Windows spinning wheels at login after a windows update. Possible instability which I think have fixed by lowering ram frequencies. So for right now got it going with fixed voltages and speedstep disabled and svid communication disabled. So if anyone has experience with these kinds of mods and how to tweak the bios settings for stable voltages please share. Fwiw fixed frequency voltage mode is ok by me if all else fails.