If I install Big Sur with an unsupported nvidia

Hi all :)

I know Big Sur (and older versions) doesn't have web drivers for Nvidia, but does it mean that Big Sur won't be able to boot at all, or it will be able to run as if it was connected to an iGPU?

I think of buying a 3060ti card in a few moth (I recently bought a G-Sync monitor from a friend, so Nvidia cards have an advantage in this aspect).

Now I don't do anything too heavy on mac os with the GPU, so I really don't care if it doesn't deliver all the power 3060 can give, but enough power to run 2 screens (2K 144Hz and 1K displays) properly.

Now I 10.15.7 with RX570. If what asked above is not possible, will transferring this GPU solve the problem? Will it make the installation even harder than it is now?

BTW, sorry about my English..

Thanks :)