WhateverGreen is the way to go for me. It also allows me to inject CFG_USE_AGDC via an SSDT, which means one less edit to perform on every OS upgrade.Dell doesn't support DP 1.4, you still have to connect 2 cables.
5K with RX580 and 10.12.6 isn't plug&play either. I had to remove the IDs 0x67DF1002 from AMD9510 and AMD4100 to force macOS to load the kexts AMD9520 and AMD4200 instead and use framebuffer Gueriba.
That might change with WhateverGreen and Lilu kexts, but I didn't have time to do any further testing.
How do you do that?WhateverGreen is the way to go for me. It also allows me to inject CFG_USE_AGDC via an SSDT, which means one less edit to perform on every OS upgrade.
There's an SSDT sample in the WhateverGreen FAQ you can use as a reference. SSDT's are quite complicated but you essentially use RehabMan's patched MaciASL to generate/edit them, and then copy them over to EFI/CLOVER/ACPI/patched. After you understand that piece, it's as simple as adding the proper config settings per WhateverGreen.How do you do that?
With WhateverGreen my RX580 works OOB, though without 5K support (Dell screen appears as two monitors) and Luxmark gives only 300 points. I have to test this again with a fresh install and various SMBIOS settings.
* Intel ACPI Component Architecture
* AML/ASL+ Disassembler version 20161210-64(RM)
* Copyright (c) 2000 - 2016 Intel Corporation
* Disassembling to non-symbolic legacy ASL operators
* Disassembly of iASLYzPS8Z.aml, Sun Aug 6 15:04:18 2017
* Original Table Header:
* Signature "SSDT"
* Length 0x00000138 (312)
* Revision 0x01
* Checksum 0xB8
* OEM ID "shiloh"
* OEM Table ID "GFX1"
* OEM Revision 0x00001000 (4096)
* Compiler ID "INTL"
* Compiler Version 0x20161210 (538317328)
DefinitionBlock ("", "SSDT", 1, "shiloh", "GFX1", 0x00001000)
Name (_ADR, Zero) // _ADR: Address
Method (_DSM, 4, NotSerialized) // _DSM: Device-Specific Method
If (LEqual (Arg2, Zero))
Return (Buffer (One)
Return (Package (0x0C)
"PCIe Slot 1"
Name (\_SB.PCI0.PEG0.PEGP._STA, Zero) // _STA: Status
GFX1 disables native GPU power management, why?here's the SSDT I use to rename my slot 1 GFX card's PCI identifier from PEGP to GFX1 and also add some extra properties.