The most typical AMD Radeon card for Mac HDMI port is inactive.
Works out of the box in macOS Mountain Lion/Mavericks/Sierra/High Sierra/Mojave/Catalina/Big Sur/Monterey. macOS Lion also supported with extra drivers.
System requirements:
- Apple Mac Pro 3,1 (2008), Mac Pro 4,1 (2009) or Mac Pro 5,1 (2010-2012)
- Apple Mac Pro 1,1 (2006) and Mac Pro 2,1 (2007) are also supported after installing Mac OS X 10.9 (Maviericks) or newer
- installed Mac OS X 10.8.3 (Mountain Lion) or newer
- native support by macOS Mojave/Catalina/Big Sur/Monterey, no drivers needed
Key features:
- compatible with macOS and Windows (via BootCamp)
- supports Apple boot screen (gray screen with Apple logo on startup) on DVI and miniDisplayPorts (on 4K displays and miniDisplayPorts boot screen is not available)
- uses internal Mac Pro power supply
- supports PCI Express 2.0 link under macOS and Windows (on Mac Pro 4,1/5,1)
- supports 3 displays simultaneously: 1x dual-link DVI-I, 2x miniDisplayPort 1.2 (HDMI port is inactive), analog displays supported
- supports 4K@60Hz on miniDisplayPort ports and 4K@30Hz via DVI
- supports OpenGL, OpenCL and Metal in applications and games
- supports sound via miniDisplayPorts under macOS (after installing additional driver)
- allows an upgrade to macOS Mojave 10.14.6, macOS Catalina 10.15.7, macOS Big Sur 11.7.1 or macOS Monterey 12.0.1 or newer
Technical specification:
- graphics processor clock: 900 MHz
- memory speed: 1250 MHz
- amount and type of memory: 3 GB GDDR5
- bus width: 384-bit
- bus: PCI-Express 2.0 x16 (5.0 GT/s) on Mac Pro 3,1/4,1/5,1 or PCI-Express 1.1 x16 (2.5 GT/s) on older models