ATTENTION / WARNING
!!! PLEASE DO BE AWARE THAT THIS METHOD (MORE THAN LIKELY) IS HARDWARE SPECIFIC (DELL INSPIRON 7567 i5-7300HQ). I HAD TO DISABLE CFGLOCK VIA MODGRUB.EFI. I TAKE ZERO LIABILITY/RESPONSIBILITY IF YOU MESS UP YOUR DESKTOP/LAPTOP BY FOLLOWING THIS!!
You have to create your pre-built OpenCore folder, (I recommend updating it to the latest commit from GitHub.com/acidanthera/opencorepkg and building it via macOS terminal. Be sure you have XCODE 12 beta installed on your build machine, for extra good measure and to ensure success with the process).
Once that is updated make sure that you’ve updated necessary kexts (available from GitHub dev commits and place them into their correct corresponding folders.
Make sure you disable CFG lock in your bios via modgrub.efi (I will not go into detail on this for it is different per each machine).
Once you’re done with disabling the CFG lock on your machine, make sure you run verifymsr.efi in your OC loader. Make SURE that it shows ALL CPU cores, at that point you should have proper power management and XCPM working.
Change CPU-PM and XCPM locks from “True” to “False” in your OC config.plist.At this point if all has been done both correctly AND successfully, you should be able to / ready to run the MacOS Big Sur beta 1 or 2 installer from a USB stick on your machine.