I just bought my first raspberry pi 3. So firstly connected with HDMI mouse and keyboard,download the latest version of noob from pi site and connect the pi3 to 2amp mobile charger. First bootup went perfect so during installation of noob os pi3 just stop working and showed me black screen. Now its have been three days. I have tried changing memory card,update power adapters, tried different OS.but now succeed. On some OS pi3 shows me rainbow screen then black or blink two time green led or hang at rainbow screen. They issues have face during trying of different OS for pi three: Even tried to change in config file. Please help regard this issue if anyone faced.??