Update after getting nowhere with zwift support I decide to bit the bullet and go green I bought a GTX1060 and the zwift is now smooth enough even on my favourite group ride bacon rolls which is the Achilles heel of my system. I now have the Ultra profile and can Zwift in 1080, 1440 and 2160 with similar frame rates with the ultra opposed to high profile with the RX 570 so it looks great.
Frame rate comparison
bacon rolls RX570 1440 high
avg 20, min 10, max 30
bacon rolls GTX 1060 1440 ultra
avg 35, min 22, max 113
TDW group ride RX570 1440 high
avg 34, min 10, max 61
TDW group ride GTX1060 1440 ultra
avg 77, min 27, max 131
Solo ride RX570 1440 high
avg 56, min 26, max 75
Solo ride GTX 1060 1440 ultra
Avg 75, min 48 max 95
The new graphics card has a lower fire strike score due to a lower graphics score.
AMD open GL is poor the difference changing only the GPU is amazing I’m so happy now its smooth. Still no explanation why the my cpu sits between 30-60% utilisation and my GPU is sat waiting for frames. If I run a game (directx11) you can clear see the CPU bottle neck CPU sit a 99% and GPU is up and down.