Hi Burr, yeah so like I wrote above the turning off object snaps thing will only have an impact in this area when you are in a drawing command, not while you are in "selection mode".

So just let me clarify, please try this:

With a maximized viewport, draw your sphere, then start the Line command.

While inside the Line command test doing the simultaneous motion with object snap turned on file a while (here you see the lag, is that correct), and then try the simultaneous motion for a while with object snap turned off. What happens with it turned off, does it behave very different?

That test should be done all while running inside of a drawing command that picks points like the line command.

If you see very different behavior with object snap on versus object snap off (again I'm just talking about within a drawing command), then that likely points to somewhat sluggish performance in reading data back from your video card.

- Michael