@Lost_N_BIOS When I type in value higher than 64 it will change back to Auto value.
As well the the ME v11 (Z370) vs ME v12 (Z390) issue, the changes with the EC Firmware being a part of the Z390 BIOS makes crossflashing unlikely.
If the right module can be found from the Z390 BIOS then maybe it can be edited/inserted into Z370?