Hello! It sounds like you're having some issues with your PC not displaying anything on the screen and the LED lights not working properly. Here are a few troubleshooting steps you can try to address the issue:
1. Check Power Supply Connections: Make sure that all power supply connections are secure and properly plugged in. Ensure that the power supply unit is functioning correctly.
2. RAM: Try reseating the RAM modules. Sometimes, poor connection can lead to display issues.
3. Graphics Card: If you have a dedicated graphics card, reseat it in the PCIe slot. If you're using integrated graphics, make sure it's enabled in the BIOS.
4. BIOS: Check if the BIOS settings are configured correctly, especially the boot order and display settings.
5. Monitor: Test the monitor with another device to ensure that it's working properly. Also, check the monitor cable for any damages.
6. CMOS Battery: Replace the CMOS battery on the motherboard. A weak battery can cause display and LED issues.
7. CPU and Cooler: Ensure that the CPU is installed correctly, and the cooler is properly mounted. Overheating can cause the system to shut down or not display anything.
8. Motherboard Standoffs: Make sure that the motherboard standoffs are correctly installed and that the motherboard is not shorting against the case.
9. Reset the CMOS: Try resetting the CMOS by removing the CMOS battery for a few minutes and then putting it back in.
10. Professional Help: If none of the above steps work, consider consulting a professional technician to diagnose and fix the issue.
I hope these steps help you diagnose and resolve the issue with your PC. Let me know if you have any other questions or need further assistance!