Second external monitor not working for Dell E6420 after Windows 10 upgrade

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I upgraded two Dell E6420 laptops from Windows 8.1 to Windows 10. I use both with the same docking station connected to a Dell 2408WFP monitor and a Dell U3011 monitor. The laptops have two display adapters: Intel HD 3000 and NVIDIA NVS 4200M.

Laptop #1 came out of the upgrade working fine -- plug it into docking station and both external monitors work and the laptop screen sleeps.

Laptop #2 won't display anything on the 2408WFP monitor unless I go into Device Manager and disable the Intel HD 3000. But then the laptop display won't shut off (displays blank screen but stays on) and I lose the computer sleep option from the start menu. Enable the Intel HD 3000 and I get back the sleep capability but lose the 2408WFP again.

I've tried:

  • Verified Optimus is on in BIOS.
  • Updated BIOS to latest version A22.
  • Updated NVIDIA display driver. Windows said it was current but I got a more current one from the NVIDIA site.
  • Looked for a more current Intel HD 3000 driver, there wasn't one available.

BIOS and drivers are either the same or newer in Laptop #2, and the only other difference is that #2 has Windows 10 Pro while #1 has Windows 10 Enterprise.

EDIT: Redoing the upgrade to Windows 10 resolved the problem, but then after I used the computer off the docking station, when I put it back on the docking station the problem was back. I'm looking for a better solution than reinstalling windows every time I take the laptop away from my desk.

tdykstra

Posted 2015-10-14T03:39:08.393

Reputation: 73

Answers

0

I suggest to repeat the installation (upgrade Windows 10 to itself), using a full Windows 10 installation media :

harrymc

Posted 2015-10-14T03:39:08.393

Reputation: 306 093

The fix was short-lived -- after I used the laptop off the docking station the problem returned. – tdykstra – 2015-10-26T14:38:27.063

Hmmm, something went wrong during the upgrade on this laptop (but you already know that). Do the two laptops have identical setup as regarding hardware and installed software? – harrymc – 2015-10-26T15:03:47.687

Hardware is identical. Display and Intel adapter drivers are identical, NVIDIA driver is 2 months newer on the problem machine. Bios is A22 on the problem machine and A16 on the one that works correctly. – tdykstra – 2015-10-27T01:54:45.470

You might try progressively to duplicate the setup. The display driver is the easiest. The BIOS should be done with great care and only as last resort, since if botched this will require professional help to get the computer working. – harrymc – 2015-10-27T06:47:01.523

The problem is turning out to be intermittent -- out of the blue it started working again without my having taken any new action. Matching drivers is an idea that had occurred to me, but where the drivers are different, the problem machine has the newer one, and especially in the case of the BIOS I don't want to go to an older one after having installed the latest. I really appreciate your follow-up, you definitely earned your bounty on this one. I think for now until it's time to get a new computer I'll live with it as-is and flag this as answered again. – tdykstra – 2015-10-28T01:49:36.223

Thanks. FYI: A large update for Windows 10 is scheduled for November, which might with a bit of luck improve the situation. – harrymc – 2015-10-28T08:54:16.987