I just bought a Sapphire Nitro+ Vega 64 and installed it into my 2700X rig (X470 Auros Ultra Gaming mobo, 16gb Vengeance LPX 3000mhz Ram) but when I turn it on it looks like it is going to boot but gives no output on screen and the keyboard and mouse lock up with no lights but the PC has lights.
I installed both my R9 390 and the Vega 64 at the same time and when it boots with the 390 I am able to swap over to the Vega 64 with no problem on DP until I reboot when it hangs again, and was able to test with 3DMark on the Vega 64 (Firestrike 18,000)
I have updated the BIOS and cleaned out the old video drivers using DDU and put on the latest 18.11.2 ones
I have also tried different PCI slots
I looked and one suggestion was to disable fast boot and PCI-E management but no change