Sebastien,
I believe the following is the information you are looking for:-
Beocenter 6-23. Is it DVI-I? DVI-I connector/audio L-R in
Beosystem 3. Is it DVI-D? 2 x DVI-D Female
Beovision 4-50 Is it DVI-D? 1 x DVI-D Female (24 pin)
Beovision 4-65: Is it DVI-D? 2 x DVI-D Female
Beovision 7-40. Is it DVI-D? 1 x DVI-D Female