I need to get 2 video cards in my Mac Pro 5,1. Problem is the Mac Pro has only 2 power cords, and most modern video cards need two power cords. So question is, what are the most powerful cards that require only one power cord. Super bonus points if the cards are single slot. The original ATI 5770s only require one plug and you can get 2 of them in there. Question if there are more modern cards that can do this? I think the AMD Radeon R9 Nano would work, power wise, but does anyone know if it will work in the Mac Pro?