AMD Radeon R9 280X 3GB 384-Bit GDDR5 PCI Express 3.0 Video Graphics Card for Apple Mac Pro, OS X AMD Radeon R9 280X 3GB for APPLE MAC PRO 2008 to 2012 3,1 4,1 5,1 Includes required Mac Pro power booster cables & installation instructions 3GB 384-Bit, GDDR5 Support up to macOS 10.13 High Sierra for MAC PRO 2010, 2012 at this time 4 Display 4096 x 2160 maximum resolution