I have an Acer Aspire XC-603 desktop computer. The computer runs 64-bit Windows 8.1. All available Windows updates have been installed.
What has been mysterious during the years that I've been using the computer is that often the system gets stuck at boot screen or after I've shut down Windows. During this time, the CPU power LED is on.
Often at boot, either a screen with the Acer logo or a blank screen shows continuously and Windows does not load. Sometimes striking Ctrl + Alt + Del makes the computer reboot and usually Windows loads only then. Often I must push the power button for a few seconds to shut down power.
Often after trying to shut down the computer normally by choosing Shut down in Windows, the OS seems to shut down but the computer keeps on running showing a blank screen. I once left the computer at this state to see whether it does this for a certain period of time. After a few hours, the system was still running with a blank screen.
There isn't any apparent reason as to why this happens. The behaviour seems random. Why does it happen?