1. On the Day of Pentecost. (Acts 2:1-4.)
2. At Samaria. (Acts 8:14-19.)
3. Saul, later called the apostle Paul. (Acts 9:17.)
4. At Cornelius' house. (Acts 10:44-46.)
5. At Ephesus. (Acts 19:1-2, 6-7.)
In all these cases of receiving power, except maybe at Cornelius' house, the people were already believers, and even at Cornelius' house, belief probably came at least an instant before the power came upon them. This means an interval, even if seconds, or even if a split-second.
In all cases except at Samaria, speaking in tongues was specifically mentioned as a result. In Samaria, we know something strongly supernatural and tangible was evident, and because of the other four instances, it may be a safe but not totally certain conclusion that speaking in tongues also happened there.