I finally have everything working, including audio. I stubbed my toe multiple times but I was able I resolve most of the gotchas.
Here are my lessons learned:
- The memory MUST be configured as single channel or it won't work. I believe this has to do with the fact that the default UniBeast profile is for an iMac, which only have 2 memory slots.
- High Sierra has native support for NVMe M.2 devices, but the macOS disk utility will not recognize the device if it is the only SSD in the system. You'll need to plug in a spare SATA device to initialize the volume. Once this is done, you can remove the SATA device and macOS will find the volume for the OS install.
- My card was an EVGA Geforce GTX 1060. There was absolutely NO way I could make it through the original install unless the card was completely removed from the system. Once the initial install was done, I was able to install the Nvidia web drivers and boot up with the GPU installed. An even then, the only way the card would work was with the NvidiaSingle option enabled in Clover.
- Things went much more smoothly after I updated to the latest version of Clover.
- The UniBeast installer seems to be a bit out of date for a Coffee Lake install. Many options and settings are not optimized. For example, iMac18,3 should be used for SMBIOS profile and many helpful DSDT patches are missing.
- There are some posts on a different Hackintosh web site specifically related to Coffee Lake and installing Nvidia drivers on High Sierra that I found to be very helpful in figuring out why I was having so many issues.
- Although not completely needed, I generated CPU stepping profiles for Coffee Lake following an SSDT guide
My suggestion for anyone installing on this Mobo with an Nvidia card and/or M.2 drive is to do their homework before diving in. Apparently AMD cards are supported out of the box on High Sierra, but I wanted to go with an Nvidia Pascal card so I could use CUDA drivers for some development work I'm doing.
I can also share my EFI if anyone is interested.
Good luck to all!
P.S. My apologies for the lack of proper hyperlinks - the editor didn't allow me to embed links in my post.