Laui wrote: ↑Sat Aug 24, 2019 6:21 pmSince today I have the Raspberry 4 with 4 GB RAM. If it does not work with the power supply from the Raspberry 3? I have a USB-C adapter and a MicroHDMI to HDMI. I took out the SD card with Noobs from the 3, on it contain Raspbian & LibreELEC. Everything plugged, but nothing happens, no booting, screen keeps blank. The small red power light on the Raspi is on.
You also need the latest Raspbian Buster. Your old Pi3 NOOBS card likely installed Jessie or Stretch, which also won't work on the Pi4.