---
title: "Miyoo Mini Plus Onion OS setup — ROMs, BIOS files, and common fixes"
canonical_url: https://emudesk.com/issues/miyoo-mini-plus-onion-os-setup-roms-bios-2026
content_locale: en
source_locale: en
entity_type: issue
index_status: index
published_at: 2026-08-31T18:22:23.000Z
updated_at: 2026-09-01T00:45:02.404Z
freshness_status: fresh
---

# Miyoo Mini Plus Onion OS setup — ROMs, BIOS files, and common fixes

Your Miyoo Mini Plus has the stock firmware but games are missing, the interface feels limited, or PS1 games refuse to launch because BIOS files are not in the right place. You want to install Onion OS for the best experience.

The Miyoo Mini Plus (and Mini V1/V2/V3, Mini+, Flip) ships with a functional but limited stock OS. Onion OS is the community-maintained custom firmware that most Miyoo users install: it adds RetroArch, a better emulator core selection, a game art scraper, built-in Wi-Fi tools, port support (DOOM, Quake, etc.), and an active update channel.

Common first-setup problems:


  ROMs not appearing — Onion OS expects ROMs in exact system-named subfolders under Roms/. Files outside these paths are ignored.
  PS1 games exit on launch — the PS1 emulator requires a real PlayStation BIOS file dumped from your own console. Without it, most PS1 games fail silently.
  Neo Geo / Sega CD games won't load — these also require arcade BIOS or firmware files.