As I said above, you can disable loading of microcode in Ubuntu via the dis_ucode_ldr kernel command-line parameter by adding this to GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub and then running update-grub - but then you won't get the other benefits of the updated microcode (vulnerability fixes etc).
As I said above, you can disable loading of microcode in Ubuntu via the dis_ucode_ldr kernel command-line parameter by adding this to GRUB_CMDLINE_ LINUX_DEFAULT in /etc/default/grub and then running update-grub - but then you won't get the other benefits of the updated microcode (vulnerability fixes etc).