thanks

Like DirectX and OpenGL, Vulkan is an API. Vulkan is designed to offer greater performance, so it is generally recommended to use Vulkan when you have performance issues. It usually should improve your FPS.

Edit: If you want to know more, read this article: "Should you play Valheim using Vulkan API?"

Low level graphics API; an alternative to directX and opengl that can deliver superior performance.

Its another version of DirectX

i have a gtx 1080 so which option would be best , i have only just set up keys , not played it yet

Originally posted by MJS WARLORD:

i have a gtx 1080 so which option would be best , i have only just set up keys , not played it yet

Try it with both versions. It can be differ for each pc. You can select it at every game start.