09-02-2018 01:42 PM
I have a Lenovo Thinkpad P50 laptop that I have been using with an external Dell Ultra HD 4K Monitor P2415Q running with a resolution of 3840x2160 @ 60HZ using DisplayPort.
Initially the laptop was running Windows 10 version 1607. Under this version of Windows 10 the external display worked properly regardless if the BIOS “Graphics Device” setting was set to “Hybrid Graphics” or “Discrete Graphics.” Unfortunately, since Windows 10 now forces updates when new versions are released I was not able to stay on this version.
When Windows 10 updated itself to version 1709 using the external monitor described above stopped working. When the external monitor was plugged in (both DisplayPort and HDMI) it would briefly display an image and then go black. The Nvidia display adapter would then show as not working in the Device Manager. I spent a significant amount of time working with Lenovo technical support uninstalling and re-installing drivers etc. Nothing worked, I was still not able to use the external monitor. After some further experimenting I found that I could get the external monitor to work if I set the BIOS “Graphics Device” setting to “Discrete Graphics.” It would not work with the BIOS set to “Hybrid Graphics.”
Last week Windows updated itself to version 1803 and the external display problems have returned with some additional incorrect behaviors. As I stated in the previous paragraph under version 1709 the external monitor would only work with a BIOS setting of “Discrete Graphics” so that is how the system was set when it upgraded to version 1803. After the reboot following the completion of the Windows update I got a notification from Windows saying that the display driver failed to start. Device Manager showed that “Windows has stopped the device because it has reported problems” (see Screen Captures 1 & 2 below).
I then changed the the BIOS setting to “Hybrid Graphics”. With the BIOS “Graphics Device” set to “Hybrid Graphics” both the Nvidia and Intel adaptors show as working correctly (see Screen Captures 3 and 4 below). However, when I plug in the external monitor (both DisplayPort and HDMI it briefly displays an image and the goes black and in Device Manager the Nvidia adapter show the same error message as described in the previous paragraph (see screen captures 1 & 2).
I have tried uninstalling and reinstalling both the Nvidia and Intel display drivers. I have upgraded the drivers to the latest versions and have upgraded the BIOS to the latest version. However, the problem still persists, I am currently not able to use the external monitor at all.
Any help or suggestions would be appreciated.
09-02-2018 03:08 PM - edited 09-02-2018 03:14 PM
I am using a Dell UHD Canvas not the same model but pretty close, the major difference I have is that it is set to 2560 -1440 @ 60 hz using USBC., I have had no issues with my p50 windows 10 all the latest updates and drivers.
Have you checked the Dell support to see if it has updated firmware for the display ?
I don't know if you can run using USBC at that resolution of not, have you tried ?
One last thought,, in display settings there is a 3D mode enable/disable option have you toggled this off ?