Mac Pro 1,1/2,1 GPU upgrade I want to upgrade my Mac Pro 2,1 to El Capitan. If I go for an HD 5770 gpu does it have to be a Mac specific card. Are there any other compatible GPUs.
Yes, it needs to be a Mac specific card. The Mac specific part is basically the firmware on the card - so some cards can be purchased in the PC/Windows variant and then you reflash the firmware to make it Mac specific again.