Thanks mate , but he has not served me , the configuration that has earned me was:

hdmi_force_hotplug=1
hdmi_group=2
hdmi_mode=35
sdtv_mode=2
sdtv_aspect=1
hdmi_drive=2
/////////////

sdtv_aspect=1 for monitors 4:3
sdtv_aspect=2 for monitors 14:9
sdtv_aspect=3 for monitors 16:9