rx480 gaming x

Hi, I'm switching GPUs from GTX 1050ti to Radeon RX480 but when I boot the machine with the new GPU installed it black screens after bios. So far I have tried removing old nvidia drivers using DDU resetting CMOS updating BIOS Remounting GPU build details Intel Core i7-9700 3 GHz 8-Core...

I'm looking at a Samsung monitor, the CHG90. It has a resolution of 3840 x 1080, my current monitor runs at 3440 X 1440 and that is the highest resolution offered by all the games and programs I use, there has never been an option for 3840 x 1080. Is this resolution option set by my Windows...