I have a Dell Latitude e6440 (Intel+AMD video) with the newest BIOS A18 and the newest video drivers. It is connected to an ePort Replicator 0PKDGR. I have a Displayport cable connected between the ePort and an ACER 43" 4k UltraHD monitor at 3840x2160.
When I resume the Laptop from sleep/standby/hibernate, the screen flashes bars and sometimes completely turns off for a few seconds.
If I reboot, then everything is fine.
Might be a coincidence, but I was just trying something and switched my monitor from Displayport 1.2 to 1.1. The resolution of the display went down to 2k. Then I switch back to DP 1.2 and the issue seems to have gone away. I'm going to try this next time it happens.
So...I've seen threads on this.. I believe I tried everything on the other threads. Is it worth calling in? Would they replace the Motherboard differently for a display issue vs a cooling issue?
Is it possible that there is an issue with the eDock?
Ok...so the issue happened again today. This time, instead of changing displayport revisions, I just tried changing the display Resolution in Windows to 2560x1440. Then I changed it back to 3840x2160 and no flickering.
So it seems like something in the display drivers when it comes out of sleep.
There is no Displayport connection on the laptop. Only on the e-dock. Also, the link you provided just talks about updating drivers and bios. I already said that I did that.
Changing resolution doesn't seem to be an answer. Changing my monitor from Displayport 1.2 to 1.1, seems to fix the issue. I can't leave it as 1.1, because then the max resolution through displayport is only 2k.
So I change the monitor from Displayport 1.2 to 1.1 and then back again. This fixes it for a time until the next wakeup from sleep.
Rebooting the PC cures the issue as well.
So seems like a video driver/hardware issue on the laptop.