Second monitor not working

Hi
first I’m not good in English.
I have a Dell latitude E7440 with just on-board Intel graphic.
I bought two HDMI cables and both of them don’t work. after connecting them to the TV, laptop and TV detect the connection but nothing show on TV.
about two weeks ago I found if I reduce the output resolution, TV will show my desktop but if I connect the charger to laptop, TV will not show anything. and if anyone turn on/off any electric device, connection will disconnect for a second.
but now, I get a LG monitor and a VGA to HDMI cable, again I have the same problem but this time, if I reduce the resolution it will not work.
if I unplug the monitor VGA from the converter cable, I got check signal cable message on the monitor.

UPDATE

inxi --admin --verbosity=7 --filter --width

xrandr

Hi there,

That sounds like a hardware problem. :thinking:

Given your history on this forum, I’ll encourage you to take a look at the forum rules on How to Post and How to Provide System Information.

Please update your post accordingly if needed. Thanks.

Recommending to read this too Dell Latitude E7440 - ArchWiki and the related linked articles from it.