dGPU with SMBIOS models that lack iGPU
If you want to have Ventura with MacPro7,1 or iMacPro1,1 SMBIOS, Mac models that lack iGPU, in addition to
agdpmod=pikera in boot-args you have to add code to load the framebuffer corresponding to the AMD GPU family. This is not necessary in Monterey but it is in Ventura. Without it, a lot of users get black screen when they get to the Desktop.
For example, in the AMD 6600 series you have to add this code:
XML:
<key>PciRoot(0x0)/Pci(0x1,0x0)/Pci(0x0,0x0)/Pci(0x0,0x0)/Pci(0x0,0x0)</key>
<dict>
<key>@0,name</key>
<string>ATY,Henbury</string>
<key>@1,name</key>
<string>ATY,Henbury</string>
<key>@2,name</key>
<string>ATY,Henbury</string>
<key>@3,name</key>
<string>ATY,Henbury</string>
</dict>
In this way macOS 13 boots and runs well but the scores in GeekBench 5 and other benchmarks are lower.
Note: be sure of the PCI path to your dGPU, it can be different than mine.
The framebuffers to be loaded are different for each GPU family:
- 5500 ATY,Python
- 5700 ATY,Adder
- 6600 ATY,Henbury
- 6800 ATY,Belknap
- 6900 ATY,Carswell.