From Rare Gaming Dump

MIOS is a version of the Wii's IOS system that allows the Wii to boot into GameCube mode. It also handles patching for GameCube games that have issues running on the Wii.


Version Changes
v0 v0 is found exclusively on the Wii Startup Disc menu. This version doesn't have many differences compared to v1.
v1 Found exclusively on Launch Day Wiis and Korean Wiis.
v4 MIOS v4 is the first update released for MIOS.
v5 MIOS v5 is meant to block use of the GameCube Action Replay peripheral on Wii hardware.
v8 An update released to prevent use of the Tweezer Attack exploit.