Hi, i not used Octane more than a year ago. Last stable installed and my Blender GUI slow.
Win10 x64
GTX960 2GB - display
GTX1060 6GB - render
I try to swap cards between the two PCIE slot but no changes. Octane standalone works well. Tried a rendered viewport with simple plane or cube without any material but the whole gui slow plus my audio crackle during the render.