Motherboard replaced, GPU not working

I sent in my XPS 15 9560 with a failed CPU for repair back in January. I got it back yesterday and everything works fine, except my NVidia graphics card--while I have an Intel HD 630 integrated (which works fine), the one my games primarily use is the NVidia, which is a GeForce GTX 1050. The NVidia comes back with a code 43 in device manager, and nothing I have done to this point fixes the issue--rebooting, reinstalling the drivers, disconnecting and reinstalling the battery, etc etc etc. Has anyone else had this problem? How did you fix it or do you know what happened?

I have already talked with Dell tech support who did their own troubleshooting with RemoteAssist, but when nothing worked, said I would have to replace the NVidia. How much would this be?