First boot a rescue ISO or a live ISO - follow the guide to mount and chroot
[root tip] [recovery] Basic Manjaro Linux Rescue and Recovery
Then install the package
pacman -Syu amd-ucode
First boot a rescue ISO or a live ISO - follow the guide to mount and chroot
[root tip] [recovery] Basic Manjaro Linux Rescue and Recovery
Then install the package
pacman -Syu amd-ucode