Be sure both the TV and computer are set to Power off.
Step1. Connect VGA cable and audio cable between PC and TV.
Step2. Power on your PC, please set your PC resolution according to following format (PC support timing)
Step3. Power on the TV, press source menu to select PC source
Step4. If you connect laptop PC, the same process as Step1 and Step2, then press Fn+F3 in laptop to switch to PC source. Perhaps some laptop is not F3, please select the correct key has PC icon. Also set your PC resolution according to following format (PC support timing)
Remark: You can use only HDMI cable connect TV and PC, because HDMI can carry audio and video signal together. VGA cable only carries video signal.