I have a Dell Latitude E6420 laptop plugged into a docking station, and the dock has 2 monitors (connected with DVI).

Also note that I've installed Ubuntu alongside (dual-boot) Windows 7.

I can't get the dual monitors to work both on Ubuntu (either 11.10 or 12.04) and Windows 7.

When I run lspci | grep VGA, I get:

00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09)
01:00.0 VGA compatible controller: nVidia Corporation GF108 [Quadro NVS 4200M] (rev a1)

If I then reboot and uncheck Optimus setting in the BIOS during reboot, I'm able to get the dual monitors to work in Ubuntu 12.04 (but I need to configure them every boot in Nvidia Settings).

When I run lspci | grep VGA, I get: 01:00.0 VGA compatible controller: NVIDIA Corporation GF119 [Quadro NVS 4200M] (rev a1)

But then if I reboot into Windows (leaving the Optimus unchecked), Windows can't detect external monitors, and the resolution is unacceptably low.

I've seen on many forum posts that this particular graphics card setup causes lots of headaches. I haven't been able to resolve my problem yet.

How can I use my external display on my laptop with intel and nvidia video cards?

How to use external displays with Intel driver on a NVidia/Intel hybrid system

nVidia Optimus , Unity 3D and Dual Monitors

"Just use VGA instead of DVI" isn't an option because my dock has only 1 VGA port (and 2 DVI).

Switching the BIOS setting on every reboot and then reconfiguring the display settings every time is tedious, time-consuming, and impractical.

Do you know how to make this work smoothly?

Thanks for your help!

P.S. see also: https://superuser.com/questions/434358/dell-latitude-e6420-dual-boot-ubuntu-windows-7-optimus-graphics-problems

  • 1
    Still loking for an answer in that one too. I guess you already read that the DVI ports are connected to the nvidia card. You can run single applications on the nvidia card using bumblebee. I guess running the whole X-server on the nvidia card would be a solution but I have no idea how to do this. Aug 24, 2012 at 14:01
  • Good news. The new X-server 1.13 has a better support for hybrid graphics if you use it in combination with Linux kernel 3.5. Nvidia is working on drivers that use those features. So there is hope for us. X-server 1.13 and kernel 3.5 will be included .in Ubuntu 12.10. Hope Nvidia finishes the new driver till then Sep 14, 2012 at 12:25

2 Answers 2


Try disabling Optimus in the BIOS and use/install the latest nVidia drivers. If those from the repository don't work, download them from nVidia.


Please let me know how it goes; I'm about to purchase a E6520 with dock as well.

  • I think changing that BIOS setting caused problems in both Windows 7 (I'm dual booting) and Ubuntu.
    – Ryan
    Jun 7, 2012 at 21:27
  • Well :-) you can always re-enable Optimus before booting Windows while you're testing.
    – Jan
    Jun 8, 2012 at 3:43
  • 1
    Thanks, but that is not a practical option as it takes far too long to change all the settings.
    – Ryan
    Jun 8, 2012 at 16:34
  • @Ryan if you do not mind power consumption, you can stick to discrete mode. Is that what you want?
    – Lekensteyn
    Jun 8, 2012 at 17:51
  • 1
    @Jan thanks but I wasn't saying "this is taking too long to figure out" but rather that switching the BIOS setting on EVERY reboot and then reconfiguring the display settings every time is tedious, time-consuming, and impractical. I'm looking to find settings that "stick".
    – Ryan
    Jun 9, 2012 at 22:41

@Ryan, you don't actually describe what happens when you have Optimus enabled in the BIOS when starting Ubuntu, but obviously it doesn't work. My guess is that your laptop is like mine (Lenovo T430), where the Intel GPU has access to the the internal display and a VGA port, and the Nvidia GPU has access to the internal display and the two DVI ports.

I'm guessing from the fact you have to re-configure the Nvidia settings after start-up that by default it uses the laptop display and one of the monitors, and you then make it only use the two monitors?

Anyway, since you need it to work with Optimus enabled so it can work alongside Windows, you have at most three options available to you:

  1. Bumblebee (Nvidia / max 2 displays)
  2. Nvidia Prime (Nvidia / max 2 displays)
  3. Optimus Prime (Nouveau / Proper Linux Way(TM) / max 4 displays)

Bumblebee is no good for you since it only uses the Nvidia GPU for 3D offloading, and doesn't allow the Intel GPU to render to display ports that are only connected to the Nvidia GPU. I don't know enough about Nvidia Prime to be sure, but I suspect it has the same limitation as Bumblebee, even though it allows the Nvidia GPU to take control of all rendering.

I therefore suspect that your only option is to use Optimus Prime, which if it works will allow you to use your laptop display at the same time as using your two monitors. YMMV, but because of various regressions I've noticed with my laptop, I'd say Ubuntu 13.10 may be your best bet. Because Optimus Prime relies on the open source drivers, you can easily test to see if it works using a live install.

If you can't find a version of Ubuntu that works for you than you may find that Fedora 19 works — Fedora 20 and 21 probably won't because of these same regressions. I've written an article (Driving Multiple Monitors on an Optimus Laptop) that may help you along the way.

  • thanks! I no longer dual-boot the Dell Latitude E6420 laptop so can't try what you suggested, but I bet your answer will help other people!
    – Ryan
    Nov 15, 2014 at 23:31

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .