High Sierra R9 290 Dual Monitor Support?

[gateway69]

I just updated today and Im unable to get my R9 to work, im currently plugged into the motherboards graphics card. I never had issues with El Cap or Sierra.

I'm using the latest Clover. When I plug in my DVI into the AMD card the monitor goes black, If I plug it back into the motherboards DVI my screen shows up.

Included is a screen shot of what the system seems to think is on my device.

Everything else works fine (ethernet, audio, iMessage, etc).

Suggestions?

 

[Taruga]

I believe that if you disable the internal GPU, your AMD card will work fine.

If you don't want to disable the internal GPU, then check if your AMD GPU is using EFI bios or not with GPUZ (If you have Windows on that computer)

It should show you something like this (with the UEFI checkbox checked)

If you don't see the UEFI checkbox checked, then look at your AMD GPU manual, it should have Dual Bios and a button to alternate from non UEFI GPU Bios to UEFI GPU Bios.
Once you get GPUZ to display the UEFI option checked, then try changing you CSM Support in your board Bios to "Never" and I think you will get both GPUs working and both displaying screen output on Clover menu.

I think I had this same problem when I started testing the betas of High Sierra and although I got both GPUs working I ended up disabling the internal GPU because I was having software crashes on 2 Apple Apps (iMovie and Final Cut Pro) when I had internal GPU enabled.

 

[gateway69]

I believe that if you disable the internal GPU, your AMD card will work fine.

If you don't want to disable the internal GPU, then check if your AMD GPU is using EFI bios or not with GPUZ (If you have Windows on that computer)

It should show you something like this (with the UEFI checkbox checked)

If you don't see the UEFI checkbox checked, then look at your AMD GPU manual, it should have Dual Bios and a button to alternate from non UEFI GPU Bios to UEFI GPU Bios.
Once you get GPUZ to display the UEFI option checked, then try changing you CSM Support in your board Bios to "Never" and I think you will get both GPUs working and both displaying screen output on Clover menu.

I think I had this same problem when I started testing the betas of High Sierra and although I got both GPUs working I ended up disabling the internal GPU because I was having software crashes on 2 Apple Apps (iMovie and Final Cut Pro) when I had internal GPU enabled.

thanks for replying... I dont have windows so now way to run gpu-z.. I have a AMD R9 290x board.. I wonder what changed from Sierra to High Sierra.. I never had this issue before :/

 

[Taruga]

When you turn on you computer do you have display output on both monitors in Sierra ?
Or do you only have display output on both monitors after macOS loads ?

 

[gateway69]

When you turn on you computer do you have display output on both monitors in Sierra ?
Or do you only have display output on both monitors after macOS loads ?

With el cap and sierra I never saw my boot up unless I plugged the dvi into the motherboard.. with the same thing now I just get two black monitors

 

[Taruga]

OK, that was the same with me.
Now, can you tell me your AMD GPU brand and model so I can verify one thing ?

 

[gateway69]

OK, that was the same with me.
Now, can you tell me your AMD GPU brand and model so I can verify one thing ?

AMD R9 290X ..

Someone mentioned to use Lilu and Whatevergreen kext.. ?

 

[Taruga]

My GPU has a button like this:

When pressing it, it switches from legacy GPU Bios to UEFI Bios and in UEFI BIOS mode I was able to boot with both monitors and no black screen on boot. Shutdown your PC before pressing that button.
Check if your GPU has a button like that

 

[gateway69]

My GPU has a button like this:

When pressing it, it switches from legacy GPU Bios to UEFI Bios and in UEFI BIOS mode I was able to boot with both monitors and no black screen on boot. Shutdown your PC before pressing that button.
Check if your GPU has a button like that

Thanks Ill check it this evening, but I dont recall having one of those :/