Best tip I have is to change the settings to have right mouse button enter/repeat last command. Saves so much time when drafting pipe isos. But really why is 3

Best tip I have is to change the settings to have right mouse button enter/repeat last command. Saves so much time when drafting pipe isos. But really why is 3D in AutoCAD so slow even on a very fast computer with a top of the line graphics card?