How do I erase a Nintendo 64 memory card?
There are five easy ways to erase a Nintendo 64 memory card:
Option 1
Drown it in water.
Option 2
Drop it from 15 feet high.
Option 3
While turning on the Control Deck, hold down the START button on Controller #1. If the programmers utilized this feature, a Controller Pak menu should appear. This menu will allow you to view and delete the contents of the Controller Pak.
If the first option doesn't work, then the game pak will have a feature that can only be accessed from a game menu. For example, in Wayne Gretzky's 3D Hockey, you delete saved info from the Options screen.
Insert a game that uses a memory card and put it in the Nintendo 64. Hold the start button on controller 1 (it should have the memory card in it) while turning the system on. That should take you to a memory card manager screen. From there you can delete games.