I have tried many different NVIDIA driver versions (384.98, 390.87, 396.54) on different distributions (Ubuntu 16.04, Centos 7.5, and openSUSE 13.2) and all with the same result: a bad persistent flicker until I change something in nvidia-settings. This change doesn’t even have to do much. For example, the flicker will go away if I tell the rotation to invert the display, let it timeout, and revert back to the previous settings. I’m not sure what it is doing when I click apply and the screen goes blank but it seems to be the secret combination to fixing the flicker issue.
It does this at the login screen (lightdm, sddm, gdm) as well as on the desktop (KDE and whatever Ubuntu uses)
The problem you are facing that needs the bios updated to the latest version. many times it happens that if the bios are not updated, then this type of the problem appears. Try to update the bios of your Dell device and also should check the firmware version. You can check out the [url]https://babasupport.org/dell/dell-bios-update/[/url] to implement the bios resettings.
I’m not sure where the comment went but someone mentioned checking for a BIOS update. I have already updated to the latest BIOS and there was no change in the behavior.
One other thing I noticed is that it doesn’t have to be a change by nvidia-settings. If I just rotate the display with xrandr, the problem seems to go away.
Can you describe the ‘flicker’ a bit more or even attach a video?
Also, please run nvidia-bug-report.sh as root and attach the resulting .gz file to your post. Hovering the mouse over an existing post will reveal a paperclip icon.