Starting with version 3.3.6-1 of package nvidia-installer-dkms, a new tool nvidia-installer-check is included.
It can check which of the nvidia driver variants (nvidia-dkms or nvidia-390xx-dkms) supports your Nvidia graphics card.
It does that by
finding the card id of your GPU
downloading the latest information about supported card ids from the nvidia.com
comparing the data
Here are some examples of using the tool:
Your graphics card (id 1dba) is supported by the nvidia-dkms driver.
Your graphics card (id 06c4) is supported by the nvidia-390xx-dkms driver.
Use the --force option with nvidia-installer-dkms.
Then, BEFORE rebooting, install nvidia-390xx-dkms from the AUR, for example:
yay -S nvidia-390xx-dkms
Sorry, your Nvidia card (id: aaaa) is not supported by nvidia-dkms nor nvidia-390xx-dkms.