In February 2006, Apple introduced the Intel-based Mac mini (Early 2006). This model and models of Mac mini through 2009 use a different power adapter than models of Mac mini released before 2006.
The two power adapters are not interchangeable, and should only be used with the model of Mac mini they shipped with. Read on to learn how to identify which power adapter to use with each Mac mini computer.
After 2010, the Mac mini moved to an internal power supply, mercifully.