Hello!
I'm sorry to hear that you're having issues with your all-in-one PC. Based on your description, it seems like your PC is not displaying any signal on the monitor. Here are a few troubleshooting steps you can try:
1. Check the connections - Make sure that all the cables are properly connected to the monitor, PC, and power outlet. Try unplugging and re-plugging all the cables.
2. Test the monitor - Try connecting the monitor to another device such as a laptop or another PC to see if it will display any signal. This will help you determine if the issue is with the monitor or the PC.
3. Remove all external peripherals - Disconnect all external peripherals such as printers, scanners, USB drives, and other devices from your PC. Sometimes, these devices can interfere with the display and cause issues.
4. Check the BIOS settings - If the issue persists, try accessing the BIOS settings by pressing the Delete key or F2 key during startup. Check if the display settings are set to the correct display output.
5. Remove the graphics card - If you have a dedicated graphics card, try removing it and using the onboard graphics. This will help you determine if the issue is with the graphics card.
6. Test the RAM - Try removing and reseating the RAM modules. You can also try using only one RAM module at a time to see if the issue is caused by a faulty RAM module.
If none of these steps resolve your issue, it might be best to seek the assistance of a professional technician. Good luck!