AMD R9 295X2 review: 500 watts of cool-running 4K gaming goodness with a price tag to match | Extremetech
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
Radeon R9 280X 3GB Metal GPU Video Graphics Card for Mac Pro 4K Boot Screen 7950 | eBay