Flashing R9 280X for boot screens/PCI System Information | Page 21 | MacRumors Forums
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
PowerColor TurboDuo Radeon R9 280 3GB GDDR5 PCI Express 3.0 CrossFireX Support Video Card AXR9 280 3GBD5-T2DHE/OC GPUs / Video Graphics Cards - Newegg.com
PowerColor Radeon R9 280X 3GB GDDR5 PCI Express 3.0 x16 CrossFireX Support Video Card AXR9 280X 3GBD5-DHE GPUs / Video Graphics Cards - Newegg.com