Display turn Black, after many times turn off and on, sometimes works
My Thunderbolt Display (A1407) stays black after connecting it to my iMac.
After many times unplug the power cable and plug it in again, the picture came back. Unfortunately, it disappears after 30 minutes and does not come anymore. The picture was good, no mistakes.
What could it be? Power cable to the iMac or power supply?
Has anyone else had this problem and how did you fix it?
What would be the most sensible to replace?