A very new TEST development version of Retropie for the Raspberry Pi 4 has dropped, its an unsupported version, meaning it literally is to fuck about with, and from what we have read, its no where near polished – but remember, before you start bitching the developers ARE NOT Paid nor endorsed or associated with Raspberry Pi, hell from what we hear they didn’t even get any Pi 4’s sent to them from Raspberry Pi Foundation !

Source (REDDIT)

An unsupported test build of RetroPie for the Raspberry Pi 4 by the official RetroPie team.

The default login/ssh/ftp/etc for this image is; User: pi Password: raspberry

The image is 706 MB in size and is in .img format (zipped).

Note for 4k displays:

The Pi4 video drivers are not yet optimized for 4k displays. Make sure you’re using hdmi 0 (the micro hdmi port next to the usb-c power port). Edit your config.txt and paste this to force it to 1080p:

hdmi_ignore_edid=0xa5000080

(Thanks to Kabael for the tip!)

This by NO MEANS a completed finish release, infact its one of the EARLIEST releases, and will no doubt have totally changed before an official public release build is ready – that being said – there are many entitled people out there who for some fucked up reason think they should have their free software NOW as they bought a Pi 4 (remember – Raspberry Pi ARE NOT Retropie) – so guys please be patient this is a perfect step in the right direction and some great news to be breaking at the start of 2020 – the year of the Pi 4B………..