Ubuntu won't start properly after installing new GPU

I recently acquired a new GPU for my computer. I installed it and tested it (on Windows 10), and it works fine. Now I tried starting Ubuntu on my computer, but it gets stuck on "Started GNOME...". I previously had amdgpu installed on my system, and that worked great with my old graphics card. But with my new graphics card, after removing the amd drivers, it isn't working. I tried installing the recommended Nvidia drivers from the graphics-drivers ppa, but that doesn't work at all. Even proprietary drivers won't work. If anyone knows anything that could help, I would be very grateful.

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