I'm working on a sketch for an extruded feature in a part. As you can see on the screen print, the vertex is coincident with a curve (which is also coincident with another curve).
When I zoom in (2nd screen print) the vertex moves off the curve, and the two coincident curves (dotted line and orange line) diverge.
Is this a setting somewhere? My PC has an i7 processor with 32 GB RAM and a 4 GB Nvidia Quadro K4000M graphics card so should be able to handle accurate graphics.