Just wanted to say thanks, this method still works!

Had to move over to a different OS ahead of the 8,2 losing security updates as High Sierra will become unsupported as of September, so chose Ubuntu.

Couple of minor points for people who may be following along in 2020;

I used rEFInd 0.11.4, which is currently the latest version (circa 2018), and I wouldn’t use the install-refind script, just install it manually;

Mount your EFI partition, if necessary make an EFI folder inside, and make a BOOT folder inside that. copy the refindx64.efi here, but rename it BOOTX64.efi

Add a drivers folder at this level and just move all the drivers from refind here, just in case. To be sure this would work, I created a folder one level up called refind, and put the drivers folder here too, in case refind went looking somewhere else.

The 4 magic lines you add disable the discreet GPU (for the 8,2, either an AMD 6750m or 6770m). Mine doesn’t work properly any more, so I’m happy to disable this.

All the other commands work, and all the hardware works out of the box, barring WiFi. Thankfully, I’m running 18.04.2 LTS, so getting WiFi working is simply enabling it under proprietary drivers.

Everything else seems to work as you’d expect, very happy!

Thanks for this post, this laptop still has life in it.