So what are my odds of swapping a 3070 ti with a Radeon 6900 xt without reinstalling? Theoretically it should be fine, uninstall nvidia-dkms install amdgpu packages. Reality often doesn’t match theory, however.
I’m fine for reinstall, but time saving wouldn’t hurt either. Any thoughts on specifics I need to do?
While using your old novidea card, uninstall all novidea stuff, delete all configs related to novidea, shut down your computer, unplug it from power, disconnect the monitor(s).
Swap the cards, reconnect everything. Turn it back on. Hopefully, everything will work fine.
If it doesn’t boot, there is some step I forgot
Have a USB stick with an EndeavourOS live image ready, just in case. Not to reinstall, but to use a web browser in it to come here and ask for further help, and/or chroot and install any missing packages. Though, I see no reason why you wouldn’t at least be able to boot to TTY.
Should be able to remove all nvidia related packages shut down and remove the card. Install the new card and boot up on the new card. It will boot on the amdgpu kernel module. Hopefully there are no issues but be prepared just in case. So save whatever you need to in case a reinstall is necessary.
Edit: As @Kresimir said make sure you have power disconnected and you ground yourself while handling any of the components you remove and install while inside & outside the case. The 6900 XT is too expensive of a card to have it damaged installing it.