Sapphire RX 570 8gb Nitro+ - HDMI not working (Black Screen)

[dk1306]

Hey guys,

I have an issue with this graphics card, meaning the HDMI ports are not working. This card has 2xDP, 2xHDMI, 1xDVI
What I've tried was differrent framebuffer: Ornicoco, various SSDT Implementations with connector-priority, connecttor-count and so on.
No luck. MY other card Sapphire RX 590 8gb Nitro+ is working perfectly, it even has the same device-id.
Can you help me

Attaching my EFI folder.

Note: This is about my other Machine
Specs:
OpenCore Bootloader
iMacPro1,1
Catalina 10.15.7
Mobo: P6T Deluxe V2
Graphics: Sapphire RX 570 8gb Nitro+

I would very appreciate that, if you could point me in the right direction of fixing it.

Thanks

 

[dk1306]

Does anybody has clue, what else I could try?
Dp, even dual dp are working perfectly, but hdmi and dvi not.