[SUCCESS] Gigabyte C246-WU4 and C246N-WU2 workstation(-lite) motherboards

[etorix]

For my first post, I have the pleasure to report success with two C246 motherboards from Gigabyte, ATX-size C246-WU4 and Mini-ITX C246N-WU2. I do not intend to make a fully detailed guide: It suffices to follow the official OpenCore guide (0.6.4 as tested) for Z370/Z390, except for three points, only the last of which is critical.

1. SSDT-AWAC is not needed: The boards have no AWAC but a plain old RTC; workstation chipsets err on the conservative side.
   
   
2. "Booter>Quirks>ProvideCustomSlide" may be turned off. The debug version of OpenCore reports that all native slides are good, and indeed the boards can boot without this quirk.
   
   
3. MATs are not supported (again, a conservative design): Under "Booter>Quirks", set "EnableWriteUnprotector" to True and, accordingly, both "RebuildAppleMemoryMap" and "SyncRuntimePermissions" to False.
   If set the other way around, as in the guide, you will boot and install OS X but the hack will break after a few reboots, complaining about an invalid frame pointer and locked register CR2.

That's it!

The latest firmwares, F6g and F2c, expose all required BIOS settings, including removing the CFG Lock, so quirks "AppleXcpmCfgLock" and "DisableIOMapper" are not even required if BIOS is set according to OpenCore recommendations.

The boards have a single USB controller for all ports, so a custom map is required. For C246N-WU2, it suffices to disable HS02, the USB 2.0 personality for the rear USB-C port to be in the clear. C246-WU4 takes a little more custom work: Obvious victims are HS01, HS02 (2.0 from the red USB 3.2 ports), HS06/SS06 (on-board USB-A) but you'll still need to sacrifice HS07 or HS08 (2.0 from the rightmost USB 3.0 ports; the middle ports are on an internal hub and share HS03/SS03) if you use both internal headers (HS13,14 for 2.0, HS/SS04,05 for 3.0).

Bonus: Thunderbolt!

The C246-WU4 has a Thunderbolt header. I have flashed a CG-Titan Ridge v.1 according the guide in the Designare Z390 thread, and made a custom DROM (I recommend using ThunderboltUtil to be sure to "enable the switch at port 7", whatever that arcane means…). With that and the two addtional SSDT, DTPG and the custom DROM, Thunderbolt 3 works, with hot-plug. (Caveat: I only have one Thunderbolt 2 drive and the Apple Thunderbolt adapter to test; no display.) Of course, one also gets an additional USB controller and two ports. Plugging the USB cable to a motherboard header is not required, only the Thunderbolt cable.

The C246N-WU2 has no Thunderbolt header. I tried the card nevertheless, with the SSDTs and a shortcut between pins 1 and 3 of the Thunderbolt header on the card. USB works (curiously, with a different IORegistry identity than on the C246-WU4), but Thunderbolt does not. If a Thunderbolt device is present at boot, it will show up, but there is no hot-plug and no coming back once the device is ejected.


I have mostly focussed on Mojave because I still use one critical 32-bit application, but Catalina and Big Sur appear to work. OS X identify my ECC RAM. I do not have the micro-ATX C246M-WU4, but I suspect that this board would work in the same manner as its two siblings, probably also including Thunderbolt.


Thanks to the awsome folks who have made up the Thunderbolt patches, tools and guides, and to the (*) Acidanthera team for OpenCore and its extensive documentation!

(* adjective missing because their work is beyong superlatives)

 

[Gogeta-Blue]

thank you for all the info, it was very helpful, it really helped me a lot, i’m writing this message for 2 reasons, 1 or first is obviously to thank you and the 2nd one is to informe you and others that i do have the mini board that you mentioned at the end of your post and the board does indeed works with the latest version of mac os big sur and open core, i’m using the latest bios, so you can add this board C246M-WU4 to your compability list as working and confirmed, thank you

 

[etorix]

Thanks for the information!
I'm pleased that my post was useful, even as C246 boards are getting a bit old. Maybe this can also serve as a starting point for W480.

While updating OpenCore I experimented with other settings but could not further streamline the configuration or reduce the number of quirks. The best I can arrive to remains
Enable WriteUnprotector=true
ProvideCustomSlide, RebuildAppleMemoryMap, SyncRuntimepermissions=false
All other quirks according to Dortania's guide, up to 0.6.9 as of this writing.
iMac19,1 SMBIOS (haven't tried iMac18,3 for High Sierra).
No issue with Mojave, Catalina, Big Sur. It just works.
And, for the fun of it, I have a PCI (not 'e'!) Firewire card (TI chipset) in the PCI slot of the C246-WU4: This oldie works out of the box.

 

[Gogeta-Blue]

i have another system a z490, i was going for the z590 when it first came out but i wasn’t sure if that chipset was going to work on hackintosh because the new igpu and cpu architecture, but it seems i did good by getting the z490 with an 10900k instead of a z590 with an 11900k, the reason why i choose the gigabyte board was because i have 2 gigabyte 5700 xt and i wanted a gigabyte board to match brand with the cards, also the board has 2 pci-e slots , so i can install both cards, the first pci-e works at 16x but when you install a 2nd card then both card works at 8x each, after running all kind of gaming benchmarks. video encoding apps etc there is almost no drop in performance from 16x to 8x

i have had many diferent high end systems during the course of the years, this board will do just fine for hackintosh until apple ends support for intel macs or untill the board dies, what ever it come first

i do have a 3090 with the z490 and the 10900k , i will use that one for gaming in windows and the other one for mac os

i know the z490 also works for hackintosh but unfortunstely that board has an unsupported nvidia card

but i’m more than happy with at least having one system with mac os

i will check to see if i can improve anything based on the new info that you wrote

take care, thanks