What are some potential signs of a failing power supply unit (PSU)?

Random shutdowns and failure to boot are definitive signs of a failing power supply unit (PSU). When a PSU starts to fail, it may struggle to provide sufficient power to the components of the computer, leading to unexpected shutdowns, especially under load when the system requires more power. Additionally, if the PSU cannot deliver adequate and stable power, it can prevent the computer from booting entirely, as the motherboard and other components may not receive the necessary voltage.

The significance of these symptoms lies in the PSU's critical role in delivering power to the entire system. If it is not functioning correctly, the whole computer's performance and stability are compromised. This makes random shutdowns and boot issues primary indicators that warrant further investigation into the PSU.