Voici quelques infos en plus :
le lien ou je me suis procurer l'écran : https://www.amazon.fr/Compatible-Raspberry-Modèle-Screen-Tactile/dp/B01CNLYL1C?ref_=ast_bbp_dp
l'écran est simplement superposé à mon raspberry pi donc pas de sortie hdmi , peritel ou vga
mon config.txt:
uncomment if you get no picture on HDMI for a default "safe" mode
#hdmi_safe=1
disable_overscan=1
uncomment to force a specific HDMI mode (this will force VGA)
#hdmi_group=1
#hdmi_mode=1
Sound output. Set to 0 or comment for autodetect, 1 for DVI, 2 to force HDMI.
#hdmi_drive=2
Using /etc/modules is deprecated and no longer supported on 4.4 kernel
So manually enable audio
dtparam=audio=on
config_hdmi_boost=0
audio_pwm_mode=0
force hdmi while the tv can take time before sending the signal on the hdmi output
#hdmi_force_hotplug=1
uncomment for composite PAL
sdtv_mode=2
uncomment for lirc-rpi
#dtoverlay=lirc-rpi
if you plug your tv at the same time as your rpi and that the rpi switches from the hdmi or give a low resolution because tv had no enough time to initialize it
boot_delay=3
uncomment if you don't want the rainbow at startup
disable_splash=1
default CEC name
cec_osd_name=recalbox
Overclock
gpu_mem_256=128
gpu_mem_512=256
gpu_mem_1024=448
avoid_safe_mode=1
kernel=zImage
Raise the first security limit up to 70° instead of 60°
temp_soft_limit=70