Catalina w/ Clover + ASRock Z390 + i9-9900KF + Sapphire Pulse Vega 56

Parts:

• Motherboard: ASRock Z390 Phantom Gaming-ITX/ac (https://www.asrock.com/MB/Intel/Z390 Phantom Gaming-ITXac/index.asp)
• CPU: Intel i9-9900KF with Dark Rock Slim cooler
• Memory: Corsair Dominator Platinum 32GB (2x16GB) DDR4 3200MHz C16 Desktop Memory
• Graphics card: Sapphire Technology Technology Radeon 11276-02-40G Pulse RX Vega 56 8GB HBM2 HDMI/ Triple DP (UEFI) PCI-E Graphics Card
• Disk: GIGABYTE AORUS SSD NVMe Gen4 M.2 2TB
• PSU: be quiet Straight Power 11 650W
• Case: NZXT H210 (ITX form factor)
• Display: Dell UP2414Q (4K, DisplayPort 1.2, HDMI)
• WiFI: Dell DW1560 Broadcom BCM9 4352Z, M.2 NGFF card

Working under Catalina:

• CPU, memory, SSD, the overall system, everything seems stable and fast. WiFi works perfectly.

Not working:

• Graphics: HDMI output only, DisplayPorts don't work under Mac (but do in Windows).
• Audio: no devices found.
• Bluetooth.
• Perhaps other things I haven't tested yet (e.g. USB ports).

Assembly notes:

• The Sapphire Vega 56 card does fit in the case, but it's about 3 slots thick, and because of the way the case is designed, the fans are just millimeters from the top of the PSU case, providing limited passage for air flow. I was worried about this initially, but load testing in Windows suggests GPU temps aren't a problem in practice.
• I replaced the Intel WiFi card with the Dell DW1560 after reading the latter is more Hackintosh friendly. The replacement was easy, just a couple of screws to remove the metal shield, and the card works without issues in Windows.
• The Aorus SSD has a large copper heatsink, which surprisingly, does fit into the lower portion of the motherboard's provided heatsink (the top part can easily be removed and is not necessary).
• The case is very nice, but with no optical drives or disks, there's a lot of empty space which feels wasted.
• After assembly I turned it on to check all the fans were turning freely. Everything fit perfectly and the fans are almost silent.

Installing Windows:

• I opted to dual-boot from a single SSD, so installed Windows 10 Home first, creating a 1TB partition for it.
• Initially I could not get the installer to boot, it would hang before displaying any text at all. Updating the BIOS firmware fixed this (you can do this with the BIOS setup utility and a USB flash drive).
• Bizarrely, the Windows installer would then boot, but to an orange screen with vertical white stripes. I read this can be caused by GPU issues, so used Recovery Mode to turn on "Low-Resolution Video" for the install process, which got me to a working desktop. Then I installed the latest AMD Radeon drivers and everything worked perfectly. Apparently the driver provided in the Windows 10 installer does not work with this card (go figure).
• Everything worked out of the box in Windows, as one would expect.

Installing Mac OS:

• Decided to go for a clean Catalina install. Used the latest Clover to set up the EFI partition.
• Initial boots failed, stuck after loading the APFS driver. Got stuck for an hour or two. Turned out I needed the "Fix AsRock Z390 BIOS DSDT Device(RTC) bug" patch in my clover.plist.
• The installer did not provide an option for creating the 1TB partition, and Disk Utility didn't show the free space either. I ended up using diskpart in Terminal to manually create the APFS partition. After that, the installation was smooth.
• Upon reboot, discovered the machine would only boot back into Windows (unless I booted from the original install USB). Something upset the UEFI NVRAM, I used the UEFI shell and cfg to recreate a boot entry for Clover. Even reinstalling Clover to the boot drive was not able to fix this, I had to do it by hand.

Config

kexts:

• BrcmBluetoothInjector.kext
  
• BrcmFirmwareData.kext
• BrcmPatchRAM3.kext
• FakePCIID_Broadcom_WiFi.kext
• FakePCIID.kext
• FakeSMC.kext
• Lilu.kext
• USBInjectAll.kext
• WhateverGreen.kext

Clover settings:

• Acpi: "Fix AsRock Z390 BIOS DSDT Device(RTC) bug"
• Boot: dart=0, -cdfon
• Devices: USB Inject, USB FixOwnership; Audio Inject 11
• Graphics: RadeonDeinit, ig-platform-id=0x3E920003
• Kernel Patches: AppleAHCIPort "External icons patch"; KernelPM, Apple RTC, AppleIntelCPUPM selected
• SMBIOS: iMacPro1,1 from magic menu

Unresolved Issues

Vega 56 DisplayPort

The HDMI output from the Sapphire card works, but I haven't been able to get any of the three DisplayPorts to output a signal (they work fine in Windows). I am using Lilu and WhateverGreen. When a display is connected to the port, Catalina seems to recognize it is connected, but no signal seems to be output. I suspect it's a frame buffer issue but I'm not sure. I know it's not a cable issue because the ports work fine in Windows. This is most annoying because my monitor only supports 4K/30Hz over HDMI. Help!!

Audio

No devices found. Haven't looked at this yet. Perhaps I just need to use AppleALC.kext?

Bluetooth

Nope, I'm following the thread here and have the latest versions installed, but no Bluetooth adapters appear in System Report: https://www.insanelymac.com/forum/topic/339175-brcmpatchram2-for-1015-catalina-broadcom-bluetooth-firmware-upload/?page=6