When it's up and running, go to your desktop, right click on the battery icon and select 'Power Options.' Save and exit and continue with the reboot. Go to the 'Boot' tab and disable Secure Boot. Restart your computer and hit F2 when the Dell logo comes up. The culprit is actually a stupid, hidden Dell option called 'Dell Intelligent Display.' For whatever reason, the only way to access this option is to turn off Secure Boot Mode. And for many frustrating months I thought the same thing: that it was caused by the 'Display Power Saving Technology' but it turns out this isn't the case. I had the exact same problem with the exact same computer (never had the screen replaced though).
