NVIDIA 3070 + AMD Graphics Card?

  1. file: /etc/default/grub
GRUB_CMDLINE_LINUX="radeon.modeset=1 nvdia-drm.modeset=1"
  1. file: /etc/mkinitcpio.conf

Please don’t do it like that:

#MODULES=(piix ide_disk reiserfs)
MODULES=(radeon amdgpu nvidia nvidia_modeset nvidia_uvm nvidia_drm)
MODULES="crc32c"

:warning: If 2 variables with the same name are there, then the content of the last variable will overwrite the previous.

This is correct:

MODULES=(crc32c radeon amdgpu nvidia nvidia_modeset nvidia_uvm nvidia_drm)
  1. Your last error was clearly a parsing error:
[   294.125] Parse error on line 1 of section Screen in file /etc/X11/xorg.conf.d/30-touchpad.conf
	"Section" is not a valid keyword in this section.
[   294.125] (EE) Problem parsing the config file
[   294.125] (EE) Error parsing the config file
[   294.125] (EE) 

I guess because you missed the EndSection here:

And that is why when parsing 30-touchpad after reading 21-prime.conf, this error occurs. Please correct it.