Thanks for sharing!
A couple notes after I finally got installation to work on my i9-7900x and Gigabyte Aorus Gaming 7 and using PB5:
- I had to use a blank drive that was already formatted to Mac extended journal. My fresh out of box SSD did not even show up in Disk Manager. Once formatted using a USB enclosure and my MacBook, it finally showed up upon installation boot. Basically, Disk Manager does nothing in the PB5 installation disk. This is the case for both SATA and NVME. I would think this will not be an issue once High Sierra is official launched.
- Using the OP's EFI, I got random stop errors right at the start of boot on the USB installation drive, but reset and trying again completes installation. Once installed on my SSD, no problems with boot.
- My USB ports are randomly working and not.
- As OP said, the performance of the Gigabyte is not 100%. I think this is due to the state of the Gigabyte BIOS and enabling XCMP. I have already reported some BIOS features not working, even in Windows, to Gigabyte. I'm sure things will stabilize in the near future.
- Not sure what the "Pre-Boot FileVault" boot option is on the Clover boot screen.
- Not sure if it's good or bad to use the new APFS file system. I've read conflicting reports. I had my drive pre-formated to standard extended journaled and I don't think PB5 installation changed that.
I don't know how much more I can try to do given that the Gigabyte BIOS is still beta (F7I) and there are no nVidia web drivers for my Titan xP. It also looks like we need the DEV community help with x299 USB ports. USB 2.0 works ok, but 3.0 is just totally random. I seriously doubt 3.1 works, but don't have anyway of testing.
However, I do have better confidence now that full support will eventually come, perhaps later this year with the iMac Pro launch. This is all speculative of course.