Posted 27 August 2017 - 04:21 AM
How is the monitor being connected to the computer, DVI or D-Sub? Either way, unless already tried, disconnect and reconnect both ends in case there's a bad contact.
Beyond that it's a process of elimination to diagnose. To confirm whether the problem is internal to the monitor and need a repair, you'd need to get to connect it to another source with a different cable, or substitute another monitor temporarily.
Likewise for checking cables, and inputs to see if the input you're using has the problem but the other input is OK.
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