Q.    "What limits are known of the standard Delphi controls?"

A.    There can be 16368 tabs in a Tab Control.
      There can be 5440 Items in a ComboBox.
      There can be 5440 Items in a ListBox.
      There can be 570 pages in a NoteBook control.
      There can be 16368 palette pages in the Delphi Component Palette.

      Note: Going beyond these limits may cause serious errors.