Ainars have you seen any stability issues with the Vega? I seem to have managed to make the only Vega rig which can't mine Cryptonight
They will happily do anything else, but even benchmarking Cryptonight in Nicehash causes them to lock up. That's with the blockchain driver on Windows 10.
I did manage to get both cards running 2KH/s with Cast-XMR following that guide you posted, but only for 60 seconds then they locked up again
If they lock up while mining they will keep consuming power too!
Most vexing! Going to try one on a Windows 7 board later...