A computer's clock runs even when power is cut off because the computer's clock system is usually provided by a hardware device called a real-time clock (RTC). A real-time clock is a self-contained, power-powered device that can continue to run even when your computer loses power because it has its own power supply**.
The main function of a real-time clock is to provide information about the current time of a computer system. It is usually driven by a quartz crystal oscillator to ensure the accuracy and stability of the time. The quartz crystal oscillator has high stability and reliability, and can provide an accurate timing reference over a long period of time. Real-time clocks play an important role in computer systems, as they can be used to record timestamps, schedule tasks, implement timers, and more.
The power for the real-time clock** usually comes from a coin cell battery or backup power supply on the computer's motherboard. These power supplies provide stable power to the real-time clock**, ensuring that the real-time clock will continue to function even if the computer loses power. This way, even if the computer shuts down or fails, the real-time clock can continue to count, and when the computer restarts, or returns to normal, it can pick up on the previous time record.
The computer's clock runs even when the power is lost because the real-time clock has a separate power supply**, which ensures accurate time information in any situation. This design allows the computer system to record and track timestamps at any time, enabling a variety of time-related applications. With the continuous development of computer technology, real-time clocks are constantly improving and upgrading to meet higher accuracy and stability requirements.