More than likely your computer is via . an analog signal sending something your television cannot use . Be it the resolution is too high or refresh rate is not lining up to what the television is capable of . How to fix it second monitor to the PC and tweak video settings to the television panel inside Windows . Generally the component that outputs video from a PC negotiates its capabilities . Sometimes not . The problem component as to not negotiating capabilities or its identity would be the television . Maybe the software running inside the TV wasn ' t programmed adequately to use VGA but you should be able to adjust the signal to something the TV would be happy with . Be it 720 p 1080 p and 60 Hz or less .