Help Cant Get pi3 off of rainbow screen

[rscott8650]

I have two raspberry pi3s i bout this weekend i loaded retropie into one and began building it. I finished getting retropie the way i wanted it then coppied the sd card. I went to put it in the second pi3 and all I get is the rainbow screen. If i take it out and put it in the first pi3 it works fine any suggestions?

[MaxK1]

Have a look through the "STICKY's" in the trouble shooting section. Especially this one:

viewtopic.php?f=28&t=58151