List of AMD Radeon Navi cards in Catalina That work.

macOS Catalina Beta 15.1 version 2 now includes the new AMDRadeon6000kext and supporting kexts to allow support for the new Navi cards.
Whatevergreenkext either needs to be disabled or removed or you can use this boot argument. agpdmod=pikera

List of 5700 Series Cards tested and working:
Sapphire 5700XT reference
Sapphire Pulse 5700XT
Sapphire Nitro + 5700XT
Sapphire Pulse 5700
Gigabyte reference 5700
**Gigabyte Gaming 5700XT
MSI Evoke 5700XT
Asus ROG Strix 5700XT
Asus 5700XT...

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