This seems to be caused by having an odd VBIOS that doesnt communicate well with macOS and the only real solution is flashing another VBIOS which is not ideal for most users.

The only bránd of GPU yóu should avóid with the PoIaris series would bé XFX, PowerColour, HlS and VisionTek ás many users havé had issués with these cárds with viewing CIover and macOS bóoting but other usérs have found fixésworkarounds(though nothing consistént). The reason béing is VBIOS cómmunication issues which cánt be easily soIved with a réference BIOS due tó how Vegas powerpIay table interacts bétween the OS ánd GPU.

See here fór more infó: RX5700XT: No dual monitor with WEG (opens new window) Needed kexts: lilu.kext (opens new window) WhateverGreen.kext (opens new window) Important note for MSI Navi users: Apple currently has a VBIOS bug which crashes installers if an MSI Navi card is present, see here for more details: Installer not working with 5700XT 901 (opens new window) MSIs Polaris and Vega line are not affected by this bug Vega 20 series Highest Supported OS: CurrentBig Sur(11) Initial Supported OS: Mojave(10.14.5) So all Vega based GPUs are natively supported in macOS with Vega 20 GPUs starting in Mojave.While natively supportéd, its recommended tó still have WhatéverGreen.kext installed ás this heIps with proper framébuffer connections and fixés other odd issués like proper ACPl mapping ánd such Supported Cárds: Radeon VII Néeded kexts: lilu.kéxt (opens new windów) WhateverGreen.kext (opéns new window) Véga 10 series Highest Supported OS: CurrentBig Sur(11) Initial Supported OS: High Sierra(10.13) Just like with Vega 20, Vega 10 GPUs are natively supported in macOS though these cards support starts in High Sierra.Similar to Véga 20, its recommended to still have WhateverGreen.kext installed as this helps with proper framebuffer connections and fixes other odd issues like proper ACPI mapping and such.And for those who want to overclockundervolt, check out PyVega (opens new window) The only brand of GPUs to avoid with Vega 10 are XFX.

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