1 Copper

Suddenly external monitors stopped working (XPS 15 9550)

So, I've been facing a weird problem with a few XPS 15s (9550) we have in our company. We use USB-C to double DisplayPort connector to connect the laptop with 2 monitors (Dell E2216H). The problem is sometimes suddenly the monitors stop displaying anything when a user starts his laptop in the morning. The weird part is that it was working ok last evening. So I try to change the connector and reboot the machine but nothing works. The only solution which works is to updating NVIDIA drivers. Anyone facing this issue? 

0 Kudos
3 Replies
7 Gold

Re: Suddenly external monitors stopped working (XPS 15 9550)

I'm surprised to hear that updating the NVIDIA drivers makes any difference, because the NVIDIA GPU isn't even wired to the display outputs on the XPS 15 9550.  It's a "render-only" GPU that, when activated, does all of the heavy lifting and then passes completed video frames to the Intel GPU, which is wired to the built-in display and the display outputs.  One of the reasons for this wiring design is that if the NVIDIA GPU were wired to display outputs, then it would have to be active whenever someone had an external display attached, even if there wasn't anything graphically intensive going on, and that isn't ideal for battery life.  My guess is that the NVIDIA driver installation routine essentially causes some display subsystem of Windows to be restarted in order to use the newly installed driver, and that somehow also fixes the USB-C issue.  If you haven't already, see if there's an update to the Intel GPU driver, since that's the one that would be driving those displays.

0 Kudos
1 Copper

Re: Suddenly external monitors stopped working (XPS 15 9550)

Thanks for the prompt reply. Unfortunately there was no update for Intel GPU on Dell Drivers page but there is one available on Intel website. So next time this happens, I'll try to update Intel drivers and see how it goes. I'll update here if that resolves the issue.
0 Kudos
7 Gold

Re: Suddenly external monitors stopped working (XPS 15 9550)


@AakashShah wrote:
Thanks for the prompt reply. Unfortunately there was no update for Intel GPU on Dell Drivers page but there is one available on Intel website. So next time this happens, I'll try to update Intel drivers and see how it goes. I'll update here if that resolves the issue.

If the XPS 15 9550 is like most other systems (including the previous 9530), you won't be able to install the drivers directly from Intel even though you can install the drivers directly from NVIDIA.  The Intel installer fails with an error that you should get drivers from your system manufacturer.  It is technically possible to extract the drivers from the install package and force them to install via Device Manager, but that doesn't always work well.

0 Kudos