Hi Y. I'm Greg, awarded MVP for eleven years, Volunteer Moderator, and Independent Advisor here to help you until this is resolved.
The Display driver is so important here that merely updating it is sometimes not enough. So let's try everything possible to get it working correctly:
First make sure you have updated the Display driver from the Dell Support Downloads web page for your exact Dell Service Tag from the sticker on the PC. Put it in here: http://www.dell.com/support/home/us/en/19/Produ...
To find Service Tag: https://www.dell.com/support/contents/us/en/04/...
If necessary first remove the old driver using DDU https://www.wagnardsoft.com/content/ddu-guide-t... (not necessary with Microsoft Basic driver which is a placeholder if nothing else is available) and/or install in Safe Mode with Networking (so you have internet), or Safe Mode, accessed by one of these methods: https://www.digitalcitizen.life/4-ways-boot-saf...
While there check also for newer chipset, BIOS/UEFI firmware (very important), network, sound, USB3 and other drivers, comparing to the ones presently installed in Device Manager reached by right clicking the Start Menu.
If this doesn't give you the latest or ideal driver for what you need, compare it to the driver offered by the Intel driver update Utility here: http://www.intel.com/content/www/us/en/support/...
or the Nvidia Update utility here: http://www.nvidia.com/Download/Scan.aspx?lang=e...
or the AMD autodect utility here: http://support.amd.com/us/gpudownload/windows/P...
For Display issues one fix that is working is to Roll back or Uninstall the Driver on the Display Device > Driver tab, restart PC to reinstall driver.
You can also try older drivers in Device Manager > Display device > Driver tab > Update Driver > Browse > Let Me Pick.
Then you will know you've tried everything in addition to Windows Update drivers.
Adjust the screen resolution until it fits and looks best at Settings > System > Display.
If this doesn't help then contact Dell Support as they cannot stick you with hardware that won't use a signed driver:
https://www.dell.com/support/incidents-online/u...
I hope this helps. Feel free to ask back any questions and keep me posted. If you'll wait to rate whether my post resolved your problem, I will keep working with you until it's resolved.
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