laptops have only black screen and mouse pointer after upgrade to windows 10

I have several models of dell latitude laptops (5540, 5550, 7440, 7450), all using Intel chipsets and video that have video issues after running the Windows 10 upgrade through windows update. All models had the current Dell video drivers from Dells website installed before the upgrade for that model. After the upgrade, I get to the login screen and can login, the desktop flashes for 5 seconds and then disappears, and I am left with nothing but a black screen and the mouse pointer. I can open task manager and create new tasks... windows appears to be work. Updating Drivers to dells windows 10 drivers does not fix this. Doing a clean install of windows 10 does not produce this issue. I really need to have the option to do either... I have 500+ users at 5 locations and many remote users to deal with. I saw this behavior in the Release Candidate versions, and chatter about it, but none of the solutions have worked.

Thanks