Alan has a 2011 Mac Mini that acts as his home entertainment system. Leo recommends using Plex to run it because it'll organize it really well. But the MacMini acts as a great home theater system. But Alan has to reboot it before it the screen stops being blank. Should he reset the SMC? Leo says that's a good guess. It could be that it's not powering up the first time. But resetting it isn't a touch of a button. It varies from model to model. You can also do CMD-OPT-PR to reset your PRAM. But Leo also says you don't really have to turn the Mac Mini off. It'll go into low power mode when you're not using it.
It could be a heating issue due to cold solders that need to warm up to "seat" and make a proper connection. It could also be a failing capacitor on the logic board. It is 9 years old and in 2011, Apple had some bad capacitors plague the design.
Trying a different power cable may actually work as well.
The power supply may also be failing. Power supplies can wear out over time, and a nine-year-old computer is like 100 years old in human years. It's simply showing its age.