Thanks for the information. I might buy the one you have suggested, aaron.s.markham ;)
By the way: yesterday I managed to install Kodi on my Jetson Nano and system rebooted with Kodi as default. On that situation I can perfectly watch a film or video and nano does not reboot (5V/3A). I guess that’s because Unity desktop is not running and nano has less power consumption.
I’ve installed XFCE4 (sudo apt install xfce4) that uses much less memory than Unity and I will check if it does reboot or not. It used to reboot after running Plex with the hard disk connected, because it tries to download from the internet all the covers from the music or videos I have on my hard disk (which also requires more memory). If Kodi does not reboot nano (it has much more quality than Plex to see videos) I would wait before buying a new power supply.