Mod guide · Nintendo GameCube

Your modded GameCube

PicoLoader + GekkoBoot + Swiss + SD2SP2

This GameCube has a small chip inside that loads Swiss, a game menu that plays games from a microSD card instead of discs. This page walks you through everything, step by step. No tech experience needed.

A purple Nintendo GameCube console

Just want to play?

If someone already set up the SD card for you, this is all you need.

  1. Turn on the GameCube

    Don't hold any buttons. Instead of the usual GameCube intro, Swiss (the game menu) appears after a moment.

  2. Choose the SD card

    If Swiss asks which device to use, pick the SD card option (SD2SP2).

  3. Open the Games folder and pick a game

    Move with the control stick and press A to select. Then follow the on-screen prompt to start the game.

01 · The parts

What's inside your GameCube

Five free, open-source pieces work together. You don't need to understand them to play, but it helps when something goes wrong.

Chip inside the console

PicoLoader

A small board based on a Raspberry Pi Pico. When you power on, it briefly takes the place of the disc drive to start the next program, then hands the drive back, so real discs still work.

Official project

Starter program

GekkoBoot

Built into the PicoLoader firmware (picoloader_gekkoboot.uf2). It looks on the SD card for a file named ipl.dol and starts it.

Official project

Game menu

Swiss

The menu you see when the console turns on. It lists the files on the SD card and starts GameCube games and apps. On the card, Swiss is the file named ipl.dol.

Official project

SD card adapter

SD2SP2

Plugs into Serial Port 2 on the underside of the GameCube and holds the microSD card where your games are stored.

Game Boy emulator (optional)

Visual Boy Advance GX

An app you start from Swiss that plays Game Boy, Game Boy Color and Game Boy Advance games without the Game Boy Player accessory.

Official project

02 · Boot process

What happens when you press Power

  1. Power on
  2. PicoLoader
    chip inside
  3. GekkoBoot
    looks for ipl.dol
  4. Swiss
    ipl.dol on the SD card
  5. Your games
    GameCube & Game Boy

The important part: the SD card must have a file called exactly ipl.dol. That file is Swiss. If it's missing or named differently, the GameCube just starts normally.

Buttons you can hold while turning on

Hold this while powering onWhat happens
NothingSwiss starts (from ipl.dol).
D-Pad Left or the Reset buttonSkips everything and goes to the original GameCube menu. Use this to play a real disc.
A, B, X, Y, Z or StartStarts a.dol, b.dol, x.dol… from the SD card if that file exists. Otherwise Swiss starts as usual.

These shortcuts come from GekkoBoot. See its official instructions for details.

03 · Storage

Find and remove the SD card

The underside of a GameCube showing its expansion ports
The underside of a GameCube. The SD2SP2 adapter is plugged into Serial Port 2 here, and the microSD card slides into the adapter.

  1. Turn the GameCube off with the Power button.

  2. Carefully tip the console over so you can see the underside.

    Unplug the controllers and cables first if they get in the way.

  3. Take the microSD card out of the SD2SP2 adapter.

    Some adapters need a gentle push on the card first to release it. Don't pull the adapter itself out of the console.

  4. Put it into your computer.

    Use a microSD card reader or an SD-size adapter if your computer has an SD slot.

SD CARD
├── ipl.dol← Swiss, must be named exactly this
├── Games/← your GameCube games
│ ├── Game Name.iso
│ └── Biohazard 4/
│ ├── Biohazard 4 (Japan) (Disc 1).iso
│ └── Biohazard 4 (Japan) (Disc 2).iso
├── vbagx-gc.dol← Game Boy emulator
└── vbagx/
├── roms/← your Game Boy games
└── saves/← Game Boy save files
What's on the card once everything is set up.

04 · GameCube

Add GameCube games

Use backups of games you legally own, made from your own discs. This guide doesn't link to download sites.

  1. Turn off the GameCube and take out the microSD card.

    See Find and remove the SD card.

  2. Put the card into your computer and open it.

  3. Open the Games folder.

    If there isn't one, create a new folder and name it Games. The folder name is just for staying organized; Swiss can open games from any folder.

  4. Copy your game files into Games.

    Wait until copying is completely finished.

  5. Safely eject the card.

    Windows: right-click the card in File Explorer → Eject. Mac: click the ⏏ icon next to the card in Finder.

  6. Put the card back into the SD2SP2 adapter, the same way it came out.

  7. Turn on the GameCube. In Swiss, open Games and pick your game.

Which file types work?

Use .iso files (sometimes called .gcm). That's a plain copy of the disc and the safest choice. The Swiss download also includes NKit, a tool that makes smaller, Swiss-compatible copies.

Games with two discs

Some games, like Resident Evil 4 (Biohazard 4), come on two discs. Keep both disc files together in one folder with clear names, and start the game from Disc 1.

SD CARD
└── Games/
└── Biohazard 4/
├── Biohazard 4 (Japan) (Disc 1).iso
└── Biohazard 4 (Japan) (Disc 2).iso

05 · Game Boy · Color · Advance

Play Game Boy games on your TV

A purple Game Boy Advance handheld
You don't need a Game Boy Player. An app called Visual Boy Advance GX plays these games on the GameCube.

Visual Boy Advance GX (VBA GX) is an emulator: software that acts like a Game Boy. It plays Game Boy, Game Boy Color and Game Boy Advance games. It is not the same as Nintendo's Game Boy Player accessory, so a few games may behave a little differently.

Install it (one time only)

  1. Download the GameCube version from the official VBA GX releases page.

    The file is called VisualBoyAdvanceGX-<version>-GameCube.zip.

  2. Unzip it on your computer.

  3. Copy vbagx-gc.dol to the main level of the SD card, next to ipl.dol.

    If the download includes a vbagx folder, copy that to the main level as well.

  4. Make sure the folders vbagx → roms exist on the card.

    Create them if they're missing. Use lowercase names exactly as shown.

Add Game Boy games

  1. Copy your game files into vbagx/roms.

    Files ending in .gb, .gbc or .gba work, and so do .zip or .7z files containing them.

  2. Eject the card, put it back in the GameCube and turn it on.

  3. In Swiss, select vbagx-gc.dol to open the emulator.

  4. Pick a game from the list.

    Save files are kept in vbagx/saves.

SD CARD
├── ipl.dol
├── vbagx-gc.dol← the emulator
└── vbagx/
├── roms/
│ ├── My Game.gb
│ ├── My Game.gbc
│ └── My Game.gba
└── saves/← save files

Shortcut: hold X to go straight to Game Boy games

Make a copy of vbagx-gc.dol on the main level of the card and rename the copy to x.dol. Now holding X while you turn on the GameCube opens VBA GX directly.

VBA GX's own instructions recommend an SD card formatted as FAT32, but this setup uses exFAT for Swiss. If VBA GX can't find your games, see Troubleshooting.

06 · Only for a new or empty card

Set up a new SD card

Only do this if you're starting with a new or empty microSD card, or the old one stopped working.

Step 1 · Format the card as exFAT

  1. Windows: open File Explorer, right-click the microSD card → Format…

  2. Set File system to exFAT and Allocation unit size to Default.

  3. Leave Quick Format checked, then click Start.

Mac: open Disk Utility, select the card, click Erase, choose Format ExFAT and Scheme Master Boot Record, then click Erase.

Step 2 · Put Swiss on the card

  1. Download the newest Swiss from the official Swiss releases page.

    Get the .7z file, for example swiss_r2119.7z.

  2. Extract (unzip) it.

    On Windows 11, right-click → Extract All. Otherwise use the free 7-Zip. On a Mac, use an app like Keka or The Unarchiver.

  3. Open the DOL folder and find swiss_r2119.dol (the number changes with each release).

    Use the file directly inside DOL, not the ones in DOL/Legacy.

  4. Copy it to the main level of the SD card (not inside any folder).

  5. Rename it to exactly ipl.dol.

    This is the step people miss most often.

  6. Create a Games folder for your games.

The file must be named
ipl.dol
SD CARD
└── ipl.dol← Swiss

07 · Keeping things current

Updating the software

You don't have to update anything. If everything works, it's fine to leave it alone. Updates can fix bugs and improve compatibility.

Update Swiss (easy)

  1. Back up the SD card by copying everything on it to your computer.

  2. Download and extract the newest Swiss release.

    Same as Set up a new SD card → Step 2.

  3. Delete the old ipl.dol from the card.

  4. Copy the new swiss_rXXXX.dol from the DOL folder to the card and rename it ipl.dol.

  5. Leave your Games folder and other files as they are.

Update the PicoLoader chip (advanced)

  1. Turn off the GameCube and unplug it from power.

  2. Download picoloader_gekkoboot.uf2 from the official PicoLoader releases page.

    Use the gekkoboot version for this setup, not picoloader.uf2, and never a file made for PicoBoot.

  3. Hold the BOOTSEL button on the Pico while you connect it to your computer with USB.

    A drive called RPI-RP2 appears.

  4. Copy picoloader_gekkoboot.uf2 onto that drive.

    The drive disappears by itself when it's done. Don't unplug anything while it copies.

  5. Disconnect USB, then turn on the GameCube and check that Swiss starts.

    According to the PicoLoader instructions, the light on the Pico should stay on.

Firmware file for this setup
picoloader_gekkoboot.uf2

Full official steps, with photos, are in the PicoLoader wiki.

08 · When something's not right

Troubleshooting

Tap a problem to see what to check, easiest fixes first.

The normal GameCube intro plays instead of Swiss
  • Make sure you're not holding any buttons (especially D-Pad Left or Reset) while turning on.
  • Check that the card has a file named exactly ipl.dol on its main level, not inside a folder.
  • Make sure it isn't secretly named ipl.dol.dol. Turn on file name extensions to check.
  • Push the microSD card fully into the adapter, and make sure the SD2SP2 adapter is firmly plugged into the console.
  • Copy a fresh ipl.dol from the newest Swiss download.
  • If none of that works, the PicoLoader firmware may need to be reinstalled (advanced, see Updates).
Swiss starts but doesn't see the SD card
  • Turn the console off, take the card out and put it back in firmly.
  • Check that the SD2SP2 adapter is fully plugged into Serial Port 2 underneath.
  • Check that the card works in your computer. If it doesn't, it may need formatting (see Set up a new card).
  • Try another microSD card if you have one.
My game doesn't appear in the list
  • Make sure the file finished copying and the card was ejected safely.
  • Check the file ends in .iso or .gcm. Convert .rvz files with Dolphin first.
  • Look inside the folder you copied it to; Swiss shows folders exactly as they are on the card.
A game shows up but won't start or freezes
  • Try another game you know works. If others work, the problem is that one file.
  • Make a fresh backup of the disc. Copies can get damaged.
  • Update to the newest Swiss. Newer versions improve compatibility.
  • Some games have known problems. These are suggestions, not guaranteed fixes.
VBA GX opens but can't find my Game Boy games
  • Check the games are in vbagx/roms on the main level of the card, with lowercase folder names.
  • Check the file endings: .gb, .gbc, .gba, .zip or .7z.
  • VBA GX's own instructions recommend FAT32. If the card is exFAT and VBA GX can't see it, a FAT32 card is the next thing to try. Swiss works with FAT32 too.
How do I play an original GameCube disc?
  • Put the disc in, then hold D-Pad Left (or the Reset button) while turning on. The console starts its normal menu and plays the disc.