Please check the followings:
1. Press the monitor's OSD control keys or 5-way controller and check the Input
     options to see if DisplayPort is selectable. If DisplayPort is not selectable,
     please ensure the DisplayPort cable is properly connected to both devices.
2. If the DisplayPort option is selectable but no signal appears on the screen,
     unplug the cable and plug it back in to allow the monitor to re-detect the
     connection.
3. If the issue persists, try connecting the monitor using HDMI to confirm that
     the monitor functions correctly, then attempt the DisplayPort connection again.
4. Ensure you have updated to the latest graphics card driver and motherboard
     BIOS version. If you cannot update the driver while connected via DisplayPort
     due to no signal, switch connections to HDMI if possible.
5. If possible, test the monitor with multiple devices using DisplayPort and verify
     that at least one device shows a signal. Trying different DisplayPort cables and
     cross-testing the cable with other devices may also help.
6. If the problem occurs suddenly after normal DisplayPort usage, use HDMI to
     ensure that DisplayPort is set to a resolution and refresh rate supported by the
     monitor.
If none of the above steps resolve the issue, the monitor may need inspection. Please contact our customer service team for further assistance.
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