Bon je suis rentré dans le retroarcustom.cfg , j'ai regarder les lignes de commandes.
j'ai ça : video_shader_enable = false
video_smooth = true
savestate_auto_save = false
savestate_auto_load = false
video_shader_dir = /recalbox/share_init/shaders/
screenshot_directory = /recalbox/share/screenshots/
savestate_directory = /recalbox/share/saves/neogeo
savefile_directory = /recalbox/share/saves/neogeo
cache_directory = /recalbox/share/extractions/
cheat_database_path = /recalbox/share_init/cheats/cht/
cheat_settings_path = /recalbox/share/cheats/saves/
video_font_path = /recalbox/share_init/system/.emulationstation/themes/recalbox/data/ubuntu_condensed.ttf
J'ai changé video_shader_enable = false par video_shader_enable = true
J'ai redémarrer et aucun changement....