Just plug the micro-SD card into your Raspberry pi 4 (4/8)GB (others might work but were not tested) and start playing! NOTE: First boot will take a bit longer. The screen will display the splash screen and reboot. Once rebooted, it will load the interface. Guides and Manuals:
Over-scan (fix black bars) - https://youtu.be/DeJCUQZB8b4
PS4/PS3 Controller Bluetooth Setup - https://www.youtube.com/watch?v=HddVZqno9Zs Xbox 360 Setup - https://www.youtube.com/watch?v=-52SfcluhKA
Full RetroPie Documentation - https://retropie.org.uk/docs/
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