Regarding power, even though the Raspberry Pi 3 is powered through a micro USB port, it requires a 2.5 amp power supply. But if you want to branch out, see our roundup of the best Raspberry Pi cases. You need the computer itself, a case so it doesn’t get damaged, and a power supply. The basic “official” Raspberry Pi case does the job very nicely for a low cost. The actual cost of this system depends on how much gear you bring with you. These prices come from, so they can vary considerably over time. Below is a rough breakdown of the cost of a RetroPie system as of April 2017. Now that you know what we’re going to do, it’s time to buy the necessary hardware. These are the hardware ingredients for a RetroPi computer. Step 1: Buy the hardware Benj Edwards/IDG If you stick to the platforms above, you’re sure to have a good time. The other, standalone emulators included with the RetroPie package produce mixed results that can be frustrating to configure.