Amazon.com: AMD Radeon R9 280X 3GB HDMI PCI Express Video Graphics Card for Apple Mac Pro, outperforms ATI Sapphire Radeon HD 2600, 4870, 5770, 7950, 9000, 9800 Gigabyte : Electronics
Gigabyte R9 280x OC 3GB GPU for Apple Mac Pro w/EFI, Boot screen, METAL and 4K | eBay
Radeon R9 280X Gigabyte 3GB OC Edition Can Run PC Game System Requirements