Dual Boot osx catalina 10.15.5 + windows 10 | dual GPU NVidia 1080ti + AMD RX 580 | Ryzen 2700x | Asus B450-F Strix

[ichano186]

target to have latest stable OSX ( Catalina ) on my pc, initial spec:
CPU: Ryzen 2700x
Ram: 2* 2x8GB delta-rgb-tuf-ddr4 3200MHz https://www.teamgroupinc.com/en/product/delta-rgb-tuf-ddr4 (all 32GB at 4 RAM slots)
Motherboard: Asus B450-F Strix
GPU: Asus 1080ti Strix
Storage: some SSD and HDDs
Monitor: Asus PG279Q and Dell UD2719D
PSU: Corsair RM1000x
Case: Phanteks Evolve ATX + Fans

#1 hardware

• allocate one of SSDs for OSX Catalina
• nvidia 10x won't work, so i added Asrock RX 580 8GB

* initial research reported it will work easier if the AMD GPU on the first PCI-E slot, but with two GPU at B450-F Strix -> the 1st slot will run at 8x and 2nd slot 4x speed

#2 trying to install hackintosh catalina without the 1080ti, only RX 580 at second PCI-E slot
followed snazzylabs guide

,
-> failed, perhaps miss some steps / not paying attention

2nd attempt followed techturnerlife

guide and literally just download files he provide to create bootable USB

• motherboard BIOS setting: disable fastboot and CSM
• boot from bootable USB
• at initial OSX screen, format the target SSD with macos appfs format then install catalina

-> success install OSX Catalina with open core 0.59
+ update EFI partition at the SSD with clover with content from bootable USB after login to catalina

#3 making dual gpu works for both OS
need to disable 1080ti at OSX
without disabling any PCI-E slot, cumbersome and B450-F seems not support the feature
make the both GPUs work optimum with the list of HW above for gaming at windows and also doable with OSX without plugging / unplugging GPUs or their HDMI / DP cables,
the setup:

pci-e slot | GPU | port | monitor
-------------------------------------
PCI-E 1 | 1080ti | DP. | PG279Q
PCI-E 1 | 1080ti | HDMI | UD2719
PCI-E 2 | RX580 | DP. | UD2719
PCI-E 2 | RX580 | HDMI | PG279Q

tried several easier methods found at internet, the one that works: SSDT method
ref:

SSDTs: The long way | Getting Started With ACPI

Disabling desktops unsupported GPUs(SSDT-GPU-DISABLE) | Getting Started With ACPI

my summary of following the guide to disable nvidia 1080ti at osx:

• put 1080ti back to 1st slot while keep the AMD RX 580 at second slot and boot to windows
• windows is ok with dual GPU, can have display from both GPU, for simplicity, disable RX 580 from Device Manager
• temperature comparison with single 1080ti GPU installed ~ 5 C, ok for me
• follow the guide to find 1080ti path
• dump DSDT with SSDTtime
• download SSDT-GPU-DISABLE, replace some characters with matching 1080ti path
• compile the SSDT-GPU-DISABLE -> SSDT-GPU-DISABLE.aml and put in the EFI/OC/ACPI at bootable USB
• edit config.plist at bootable USB with text editor to add the SSDT-GPU-DISABLE.aml
• boot with bootable USB, motherboard post by default with 1080ti, after the osx start to boot, it will freeze the 1080ti output, switch monitor input to the ones come from RX580 ( Dell UD2719 do this automatically )
• login to catalina and update EFI partition at the SSD with clover with content from bootable USB again
• restart and boot from the SSD

it works

not working:
audio from motherboard audio jack after using the disable GPU ACPI patch

audio jack from monitor ( both DP and HDMI ) works, but can't natively control the volume

to make windows appear at Opencore uefi, make sure windows installed with GPT partition https://www.windowscentral.com/how-convert-mbr-disk-gpt-move-bios-uefi-windows-10
thank to everyone who provide the guides / stories

 

[Aluveitie]

You can control the volume (and brightness) of your monitor with https://github.com/MonitorControl/MonitorControl

 

[ichano186]

interesting, i will check it out, thanks

 

[ichano186]

with MonitorControl, brightness control is working, not the volume one
thx anyway

 

[Aluveitie]

You should be able to set volume control it up too, it works for me at least

 

[Mrneal0216]

What kext's did you use for Ethernet? I have both of the Kexts in the Kext folder, but I keep getting no internet connection.

 

[Mrneal0216]

I was able to get it working. I realized that both kexts were not called out in my config.plist

 

[ichano186]

What kext's did you use for Ethernet? I have both of the Kexts in the Kext folder, but I keep getting no internet connection.

fwiw, SmallTreeIntel82576.kext

 

[RyzenPro]

not working:
audio from motherboard audio jack after using the disable GPU ACPI patch

audio jack from monitor ( both DP and HDMI ) works, but can't natively control the volume
thank to everyone who provide the guides / stories

You might wanna try using VoodooHDA instead of AppleALC