After some search I found this registry entry
( HKEY_CURRENT_USER\Software\GRAPHISOFT\ArchiCAD-64\ArchiCAD-64 16.0.0 INT R1\DevSupport\Main Screen DPI ) , where you can insert your exact screen's DPI (96 for example) so that when you press 100% zoom, drawing appears correctly scaled.
(Windows7 x64, Archicad16 x64)