Power supply issues are one of the three biggest issues you'll face when starting with Single Board Computers (SBCs). SD card issues, whether fake or faulty, are another and issues resulting from poor board design is the other common issues you can encounter.
Power supply issues can be tricky. You might have a noisy power supply that works with one board because it has extra filtering, but won't work with another. Or you're using that cheap phone charger because your board has a microUSB connector, and it is either erratic, or doesn't start up, or even becomes the cause of some SD card issues.
Some tips to avoid the most common causes of problems reported:
Don't power via micro USB - unless you have optimised your setup for low power requirements. Micro USB is great for mobile phones because they are simply charging a battery. It's bad for SBCs. Yes, it does work for a lot of people, but it also causes more problems and headaches over time than it is worth, unless you know exactly what you are doing. If you have a barrel jack power connector on your SBC, use it instead! If there is an option for powering via header connections, use that option!
Don't use mobile phone chargers. They might be convenient and cheap, but this is because they are meant for charging phones, not powering your SBC which has particular power requirements.
- When you are evaluating a power supply, make sure you run some stress tests on your system to ensure that it will not cause issues down the path.
- (Micro) SD card issues can be sneaky. They might appear right at the start causing strange boot and login errors, or they might cause problems over time. It is best to run a test on any new SD card you use, to ensure that it really is what it is, and to ensure that isn't faulty. Armbian provides you a simple way to do this -- armbianmonitor -c /path/to/device/to/test