Try a different signal cable to confirm you are not dealing with a bad cable.Disconnect the signal cable from both ends, wait about a minute, and reconnect it again firmly.Check the signal cable connection between the monitor and the PC's graphics card.Use the monitor's built-in controls and select the correct input port.Turn off then turn on the computer to refresh the connection.Confirm the monitor is connected to a power source.If the monitor does not show up in the settings, try these steps before changing the configuration settings on Windows 10: When the desktop or laptop does not detect the second external monitor, it could be a problem with the software, but it might also be an issue with the physical connection. How to fix external monitor connection issues via hardware troubleshooting How to fix external monitor connection issues via latest graphics driver.How to fix external monitor connection issues via Settings.How to fix external monitor connection issues via hardware troubleshooting.VPN Deals: Lifetime license for $16, monthly plans at $1 & more