Check the hdmi cable to see if there are any physical damages.
Hdmi cable not connecting to computer.
If it gives the correct output then your cable is fine.
Click the start menu on your pc.
Check the hdmi ports of your input and output devices.
Purchase the right sized hdmi cable to connect your pc to your tv.
Unplug the hdmi cable from your computer tv reboot your computer and reattach the cable.
Make sure the cable is tightly fitted at both ends.
Use the tv remote to select the hdmi port connected your pc as the video source.
You can easily do it by using the cable to connect another pc with its monitor or tv.
If it passes turn the p2717h off open the dell laptop lid.
Click the icon that resembles a gear to open the settings menu.
You should check whether hdmi cable is correctly inserted on your pc and monitor tv.
If this happens often consider getting locks for your hdmi cables or self locking cables.
Connect the hdmi cable from the hdmi port on your pc to a free hdmi port on your tv.
If not you need to replace the hdmi cable.
Check hdmi cable connections.