Installed my PowerColor Radeon VII last night on 10.14.4 Beta 6. Forgot to activate onboard video and received a black / blank screen after the Apple logo. Re-booted into BIOS, enabled onboard video and re-booted into Mojave.
Had no issues with anything initially, but while in Lightroom editing a photo, the system did lock up to where no keyboard input was working, but mouse cursor was responsive.
Re-booted back into Mojave. Went to bed right after that.
Looks like we're making progress.
If Radeon VII drivers are not in 10.4.4 Golden Master, then I'm returning the card and getting a Radeon RX 590 instead.
I have work to do - and, while I enjoy my games and can't wait to play Metro Exodus very soon, I certainly don't care if I can't play at Super-Duper-Big Pimpin'-Ultra-Max settings at 6,000 FPS in 6K resolution on my 25-foot flat panel display mounted adjacent to the wall-to-wall window of my seaside, ocean-view house, sitting on a cliff in Santorini that only exists in my fantasies.
Thus, if 10.4.4 doesn't support Radeon VII, then the RX 590 will be fine until it does.