Hi techworker1, let me try to make things a bit clearer.
First of all Bump and Normal nodes do not change the geometry. You can use them on an unsubdivided Plane.
Displacement in 2.79 works as a Bump by default.
If you want real displacement, you’ll have to set Cycles to experimental AND in the Materials Tab under Settings change the Displacement from Bump to True!
The Displacement moves vertices up and down along the surface normals, so it is highly dependent on the amount of vertices.
This is where adaptive subdivision comes in, it subdivides per pixel, so that something that is far away, get’s less vertices than something that is near the Camera.
Hope this helps a bit.
