What does the status lights D1 thru D4 on the Main Board provide information about?

The status lights D1 through D4 on the Main Board are designed to provide crucial information about the functioning and health of the system during the startup process. When the machine powers on, these indicator lights help diagnose the initial state of the hardware and indicate whether each component is operating properly or if there are issues that need addressing. This facilitates troubleshooting by giving immediate visual feedback on the system's status at that critical moment. Understanding the condition of the Main Board at startup is essential for ensuring that all systems are go before proceeding to operate further.