Can't update Nvidia drivers

I originally had a GT640 in my pc which I upgraded to a GTX1050. However I sold the 1050 and moved back to the 640 but It doesn't seem to work.

The fan spins and I think it can detect there is a gpu but I can't use nvidia app manual driver installation. My screen is black when I plug the gpu in but my screen does say "no signal detected"

I used DDU to try and remove the driver and there doesn't seem to be a gpu driver in device manager and I'm completely stuck, help would be great