I would check the power cable is inserted fully, then check PC to monitor cable is also inserted firmly.
If still same try monitor on another PC as it may be a video fault from PC.If it works OK on another PC then video card / mobo is faulty. If your PC has a video card shut down PC pull power plug out of PC and remove replace video card, quite often fixes that problem.
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I would check the power cable is inserted fully, then check PC to monitor cable is also inserted firmly.
If still same try monitor on another PC as it may be a video fault from PC.If it works OK on another PC then video card / mobo is faulty.
If your PC has a video card shut down PC pull power plug out of PC and remove replace video card, quite often fixes that problem.