I got CS5 many years ago but I just noticed that when I selected a video preset (HDV 1920x1080) and one artboard in the initial window, that two artboards were created, one 14400 px square and the other 1920x1080. I was wondering if this was a bug and had been corrected in later versions, or whether there was some purpose to this. I don't see any harm in deleting the second artboard.
Thanks in advance.
Hmm. Never noticed that. 14400 pixels sounds like the maximum extents of the drawing area. No harm in deleting that artboard, if it interferes with something in your workflow (such as exporting with artboards).