@ian57 Hey, thank you for answering, this is my configuration:

It's the same as the one in that link but I used Notepad ++ to edit the config.txt instead of that SSH thing which I don't understand much, is that the problem?
By default the Recalbox image works perfectly on my 24" Monitor, i don't know what could be the problem...

Hi, I'm having a problem with Recalbox, I want to do a Handheld Game Console project and I tried before the SD image and works perfectly with my HDMI monitor, but when I try connecting my Raspberry Pi 3 B to the Waveshare 5" HDMI Screen (Waveshare 5" Screen) the screen turns white with lines moving, impossible to see anything. I changed the config.txt file according to my screen specs (max_usb_current=1 hdmi_group=2 hdmi_mode=87 hdmi_cvt 800 480 60 6 0 0 0 hdmi_drive=1) and it's not working either, and I know it's not screen's fault because it works with Retropie and that config.txt, but I just don't want to use it because Recalbox worked so much better on my big monitor...
Does anyone know why does this happen? Thank you in advance