<< Solved >> Dual monitor setup not working with SMBIOS iMac 19,1

[vinodh]

I'm running macOS Catalina build 19A573a on the following system:

GPU: Radeon VII
CPU: 9900K
Motherboard: MSI Z390-A Pro

If I use SMBIOS iMac 14,2, then my two monitor connected via HDMI and Display Port work fine. If I switch to SMBIOS iMac 19,1 or iMac Pro 1,1, then the display connected to HDMI works but the display port screen doesn't get signal any more. I read somewhere on the forum that using the iMac Pro 1,1 SMBIOS is better to fully utilise my Radeon VII which is why I'm trying to get this working. iGPU is enabled. Same issue using the same settings on macOS Mojave.

I did a comparison between my real 2017 iMac 27" and my hackintosh and the iMac can export a Final Cut Pro video much, much faster. Any help is appreciated.

 

[hevega]

Using Disable board-id check patch on Kernel and Kext Patches

 

[vinodh]

Thanks. I’ll give it a go tomorrow. Much appreciated.

 

[psedog]

Also, since you are saying your Final Cut Pro is slower, download DVD MacX DVD and make sure it says Hardware Encoding Supported. That will show you if your iGPU is setup correctly. If it already does, try disabling your iGPU and test your export again. Someone did a graphics comparison between the different iMac version as well as with iGPU enabled and disabled. In some cases it was quicker with iGPU disabled. I would point you to the thread, but I don't remember where I saw it.

 

[vinodh]

@hevega I tried the board-id patch but it didn't work. Exactly the same problem.

@psedog I installed MacX DvD and it confirmed that Hardware Encoding is supported. This was after I switched from the iMac 19,1 to iMac Pro 1,1 SMBIOS. With iMac 19,1 Hardware encoding was not supported.

 

[vinodh]

Got it working! I disabled the iGPU but this time I stayed with the iMac Pro SMBIOS. Now both displays work. Also, hardware encoding is working as reported by MacX DVD and FCP X export times when compared when the iGPU is enabled is much faster. Seems like it's finally using the power of the Radeon VII.

Now that this has been sorted out, time to test out a few other things. Thanks for the help. It's appreciated.

 

[hevega]

Sorry, not to mention my definition, but in the signature says.

Forget the obvious.

One question about the hardware info pic above. What program use to generate that.

 

[vinodh]

That’s MacX DVD Ripper. https://macx-dvd-ripper-pro.en.softonic.com/mac

 

[foster]

Using Mac Pro 7,1 also works

 

[glofter1]

try this config .. work with Z390 / 9900K + AMD GPU.