GameCube System Cheats :
Cheats - Alternate starting sounds
by Unregistered Apr 30, 2005
While powering on the system, hold B until the message "Would you like to switch to 50hz mode?" appears. This allows you to switch the screen refresh to match that of PAL games. If playing on a PAL system, the message will be "Would you like to switch to 60hz mode?", allowing the screen refresh to match that of NTSC games.