Yes is normal as 3200mhzIs CPU frequency conversion normal?
If 10.15.2 work with your computer. You can update to 10.15.3 without any changeany changes in kernel patches from 10.15.2??
for some reason I was not able to get the installer work correctly, do you mind to share you EFI folder?Today I have success to install macOS Catalina 10.15.3 on my workstations HP Z440 E5-1660v4, Sapphear Nitro+ RX 5700 XT. All of funtion work fire with me.
Please share me. Your computer's graphics infomation. If nividia i can send efi work for install but graphics cannot work.for some reason I was not able to get the installer work correctly, do you mind to share you EFI folder?