We are trying to change a Video Card in a Mac Pro. It presently has in a NVidea Geforce 7300 which is flickering and pixelating among other issues. The client bought another NVidea Geforce although I am not yet clear of the exact model, we are trying to get this.
The second card is detected when installed with the first but it does not show so output is only through the old card. The machine fails to boot from the new card alone.
I am not very familiar with Mac so your help is appreciated.