Linux Graphics card support A1222Plus

Hi guys,

I'm a A1222 Plus user, have been since they were first generally available, last April and I like my machine.

I'd like to be able to dual-boot into Linux, too, and I know that won't work with a Radeon RX card.

Does anyone know the highest Radeon HD card supported?

I'm thinking, maybe HD7770

There is my humble article about A1222 Plus:
Look at paragraph 5.2, 5.3 and 6.
If you need amigaos + linux you have two options:

CGN 1 / Southern Islands
R7 240 (30 W), R7 250 (55 W), HD 7750 (55 W), R9 270X (180 W), R9 280X (250 W), HD 7970 (250 W)
AmigaOS with Warp3D Nova ( and later maybe also with videoacceleration if there will be RadeonHD v.5)
linux has shadow Radeon framebuffer ( i.e. doublebuffer )

TeraScale 3 / TeraScale 2
FirePro V5900, V5800 (75 W), HD 6670 (66 W), FirePro V7800 (150 W), HD 6970 (250 W), HD 6870 (151 W), HD 5870 (188 W)
AmigaOS with 2D driver, and legacy Warp3D via WaZp3D+compositing
linux with radeon kernel DRM acceleration, and Mesa 3D software.
With native SPE Debian 8 it works with Mesa 3D.