My system started acting up and I can't figure out why. Never had this problem before.
When I am in ISO view and chose anything other than wireframe, like "Realistic" panning and zooming are very slow. Even a smaller drawing does not act normal. I use a 3rd party software for modeling ductwork and piping, the drawings work fine on our other machine, so it's not the modeling software. It's also not the drawing file, I have tried other drawings that I had no past issues with but it still bogs down.
I have tried the following:
Updated video driver.
Tried different settings under "Options" "Display" and "3D Performance"
Ran AutoCad repair.
Checked and turned off all snap settings and grid.
That article was written for the 2010 products, so the names of the folders will be different in that way on your system. Also, the registry entry for the 2011 program is 18.1 (not 18.0:409) and it's 9001 (not 8001:409).
If things don't work correctly under the new Windows account, either, try this: