Video Card Compatabilities

To be able to see the "Boot Screens" -- screens that appear in a Mac when you invoke Startup Manager (aka system Selector), Recovery Mode, Diagnostics, and Safe Mode (none of which load the Graphics Acceleration Drivers) you need the card's EFI firmware to have support for what is called "Mac firmware" or more loosely "Boot Screen Support".

To have a card show a picture AFTER the login screen (when the Drivers are loaded) it needs to be at least a little bit compatible with MacOS. There has been increasing (but far from universal) support for PC-only cards in versions of MacOS 10.8.3 and later, but still no built-in support for Boot screens (unless it has been factory-made as a Mac-compatible card or User hacked for Mac firmware.

That card is an antique, and was Never supported in a Mac.

Far more capable cards for your no longer new Mac Pro are readily available on US eEBay, or at used outlets in your market. A common choice is the Mac-Firmware Radeon 5770 -- Drivers first appeared in 10.6.5.

What MacOS are you trying to run?

Good luck !! Finding a GPU for your 2008 ? I m running 10.14.6 and a GTX 780, had a GTX 1070 in my mid 2010 until 10.14 about 2 updates ago. Now also the HP printer doesn't print unless I use an older 10.14 version to print.

[Edited by Moderator]

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