Mac Mini Keeps freezing and have to manually power down and restart
I had a similar problem with my Mac mini. I tried different RAM, re-installed the OS, looked at system logs to try to figure out what was causing the problem. I got nowhere. Eventually I took it into the Apple Store to have a genius take a look, and at first it checked out fine. They kept it overnight and determined the logic board was bad. After a warranty replacement, it's working fine.