You can run Viewport 2.0 using OpenGL, DirectX 11 or OpenGL Core Profile mode. There are two ways to set DirectX as your rendering engine.
Method 1
Method 2
Set the MAYA_VP2_DEVICE_OVERRIDE environment variable to VirtualDeviceDx11 to always run Viewport 2.0 in DirectX 11 mode. See Rendering environment variables.
This environment variable overrides the user preference in Window > Settings/Preferences > Preferences > Display for both interactive and batch sessions (using the -hw2 option).