eyeing these deals posted on slickdeals but don't know much about support for the Mac pro...
Sapphire Radeon NITRO+ RX 580 4GB $200 + 3 games
PowerColor RED DRAGON Radeon RX Vega 56 $190 +1 game
MSI RX 580 8G V1 8GB $170.99 +3 games
Sapphire Radeon NITRO+ RX 580 4GB $200 + 3 games
PowerColor RED DRAGON Radeon RX Vega 56 $190 +1 game
MSI RX 580 8G V1 8GB $170.99 +3 games