Direct mode
From Virtual Reality, Augmented Reality Wiki
In Direct Mode, the display driver treats the HMD as an entity separate from the operating system and accessible only to VR apps. It improves plug-and-play capabilities and prevents numerous UX issues that occur when the OS treats the HMD as just another monitor. It also allows HMD developers to reduce latency by giving them the control over frame queuing and vsync behavior.[1]
Direct mode is supported by GameWorks VR by Nvidia.
