I have a Latitude E7470 and have connected a U2715H display to it. I am using HDMI cable as connection.
Recently I upgraded the video driver to latest 184.108.40.20627 from Dell site. And I noticed that the Dell U2715H display started blanking out and going in and out of power save.
I reverted to the older driver which never gave any of this trouble. I then disconnected the U2715 and tried the upgrade again, then a reboot. And then it works. But only for a while.
Typically twice a day the blanking and flashing power save starts. I have to disconnect the display. Power it off for a few minutes and power on and reconnect.
This is getting annoying.
I looked this up on Dell site and only symptom was with DP which I am not using. I am using HDMI.
I'm not sure if this is a laptop driver issue or a display firmware issue.
Anyone else had this strange behaviour on HDMI.
Lap tops rarely if ever need driver updates. Revert to the original driver. The update might be for later versions of your model. Check the details for the newer driver. If it ain’t broke.......
The aupport assist indicates it is for my model . I didn't update for a long time as I know that updates can break a working system.
The current driver has other issues particularily with outlook and Oracle virtualbox which are just as annoying.
BUt I will have to go back and complaing to Dell. I have 3 years service on it so they'll send someone round to replace the Mainboard or the video board probably.