Text: Nintendo initially stated that while the Nintendo 64 units for each region use essentially identical hardware design, regional lockout chips would prevent games from one region from being played on a Nintendo 64 console from a different region. Following the North American launch, however, they admitted that the cartridges contain no such chips, and the regional lockout is enforced by differing notches in the back of the cartridges.

Question: do us nintendo 64 games work in australia?
no