The newest AMD card available, the 7970 will meet all of your monitor needs and ramp up your graphics performance.

Built in DUAL Display Support. SINGLE or DUAL DISPLAY COMPATIBLE!

With a built in DVI port, Display Port and a hdmi port.

Your Mac Pro will be able to run Apple's 27" LED Cinema Displays. 

Right alongside any other monitor you may have (Not compatible with the Thunderbolt model)  

Key Features:

Bootscreen Support

PCI Express 2.0 Support

OpenGL 3.2 Support

OpenCL Support

Compatible with Windows/Bootcamp

4K Support via display port

Link Speed 5.0

Apple Boot Screen
The grey Apple boot screen is visible through the DVI port, or the display ports or HDMI.

System Requirements:

Mac Pro Model 3,1 or later, Mac Pro 4,1 or 5,1 No slow speed issues in mac pro 3,1

Lion 10.7.5, Mountain Lion 10.8+ , OSX 10.6.8, OSX 10.9.5, OSX 10.10.5 Yosemite, El Capitan 10.11.6 & Sierra 10.12

This video card can also be used in a mac pro 1,1 / 2,1 But you must have already have Mavericks running on your mac pro.

(In other words you have already worked out how to install Mavericks on your early 1,1 or 2,1 Mac Pro.)

This Package Includes:

One Radeon 7970 / R9 280X 3 GB graphics card

One 6-pin PCIe Power Cable for Mac

One 8-pin PCIe Power Cable for Mac

One Installation Manual

Note:

This Radeon HD7970 is not the official mac retail version, it is an aftermarket option. It comes in a blank box.