5.81 gb memory usable out of 8gb

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4

Then its not possible. :man_shrugging:

  1. Add more RAM :wink:
  2. Complain to the programmer of the BIOS.
  3. Try this, maybe it has any effect:
amdgpu.vramlimit=1024

Source: drm/amdgpu AMDgpu driver — The Linux Kernel documentation

This should restrict it by 1024MiB by adding it to the kernel parameter at grub.