AMD R9 280X for Mac now Available: Great value OpenCL powerhouse for Final Cut Pro & Adobe Suite - MacFinder
AMD Radeon R9 280X 3GB Video Card for Apple Mac Pro: Step up from the 7950
AMD Radeon R9 280X 3GB for Apple Mac Pro with Power Cables | #1791127043
MacVidCards AMD Radeon R9 280X 3 GB GDDR5 Video Card Apple Mac Pro BOOT SCREEN | eBay
R9 280x flashed with EFI
Gigabyte R9 280X 3GB Upgrade 1,1-5,1 Apple MAC PRO 4K, METAL, Catalina Support | eBay
Computer Components & Parts METAL Club 3D R9 280X 3GB Upgrade for 1,1-5,1 Apple MAC PRO 4K Mojave Support Computers/Tablets & Networking
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
MSI AMD RADEON R9 280X 3GB Apple Mac Pro Compatible Video Card - $395.00 | PicClick
R9 280x flashed with EFI
R9 280X only displays video on one mDP port. Does it need more power? : r/ macpro
Radeon R9 280X 3GB for Apple Mac Pro (VisionTek) *7950 7970 | #1790687502