You notice that when you move your cursor over an object it begins to lag. You've enabled/disabled your hardware acceleration, but the lag remains. If you you have xrefs in the drawing then that could be your culprit. To over come this try creating a layer filter that excludes all the xref layers Use the name filter ~*|* as seen here:
Now set the layer filter current and your issue should subside.
Thanks to my good buddy, Tom Richardson for passing this along to me.