After the computer repair shop had tried everything possible with drivers and running the Sapphire Radeon RX 5700XT Nitro+ also on other computers with the same fault they concluded that something was wrong with this GPU,s way to work properly.At its best it booted with stuttering and flickering screen.Not very nice to watch from a expensive GPU.Returned the GPU and bought a ROG Strix GeForce RTX 2080 Super and now everything works just fine.Thanks for the help.
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