Amd Rx6600 working in Monterey but nu video out in Sonoma

[jgiraltr]

I’ve got an Ivy bridge  intel core i7 3770 system 16 gigas ram main board Z77x-up5 Th -cf, I’ve instaled a brand new Asrok rx6600 challenger, and while de system works on win 11 and mac os Monterey, working every thing, when apgrading from Monterey to Sonoma System installs and starts booting with logo symbol, but suddenly it looses video out. Any tip for solving this problem?. Thanks in atvance.

[MaLd0n]

Ur processor has no avx2 and don't work with AMD GPU card after monterey. U need one haswell+.

[jgiraltr]

Thanks for your answer. Going back to my old Geforce 770 with oc legacy patcher may be a temporary fix?, or in the other hand, may my motherboard will suport a haswell processor?. Thanks

[Aaron Evans]

That symptom usually means the RX 6600 doesn’t get proper support in Sonoma by default. Monterey still included working drivers for Navi23 GPUs, but Apple trimmed support in Ventura/Sonoma. Two things to check:

• Bootloader patches: If you use OpenCore, enable agdpmod=pikera boot arg for AMD Navi cards.

• Kexts: Make sure WhateverGreen.kext and Lilu.kext are the latest versions, otherwise the GPU won’t initialize.

• SMBIOS: Use a model known to support AMD dGPUs (e.g., iMac20,1 or MacPro7,1).

• Logs: Boot with -v and see at which point the handoff to the GPU fails.

If you want full Sonoma compatibility, confirm that the current WhateverGreen release supports RX 6600. Without it, you’ll get exactly the black screen after the logo.