12-20-2019 01:31 PM
12-21-2019 04:05 AM
Sounds like you're using hybrid graphics or Intel-only on a Laptop with dual graphics and outputs wired to the discrete graphics card. HDMI / DP works but only if I9 select nvidis discrete mode.
ThinkPax X1 Extremed Gen 2.
12-21-2019 10:42 AM
@powerriegel : This thread is about an issue which happens even in discrete mode. Please see my post which opened this thread (Message 1), where I wrote this even in bold , because I knew that what you propose does not solve the issue in this configuration. Others people in this thread confirmed this, including a person from Lenovo. Please do not mix different issues in one thread, your solution is for another problem which is not the topic of this thread.
12-23-2019 12:43 AM
I am having this problem too in a T480 under Ubuntu 19.10.
Can anyone confirm if this also affects the previous generation thunderbolt 3 dock, Lenovo ThinkPad Thunderbolt 3 Dock - 40AC?
12-23-2019 01:53 AM
Actually, I have been now working for 1 hour with the laptop screen and one external 1920x1080 monitor without a problem. The only thing I did differently is that I booted the computer while connected to the docking station (earlier had booted into Windows to check if the problem persisted).
I haven't been able to reproduce the failure by booting disconnected (and I'm slightly afraid to try, to be honest).
Anyway, feel free to ask me for details on my exact configuration.
Lenovo Thunderbolt 3 Gen 2 Docking Station (not sure which firmware revision).
Intel Graphics (power saving)
12-30-2019 01:17 PM - edited 12-30-2019 01:36 PM
I also had this exact issue with my X1E (Gen1) after upgrading to 3.1.65 with Fedora 31 kernel 5.3.16-300.fc31.x86_64 and nvidia nvidia-driver-440.44-1.fc31.x86_64 from negativo.
My system is set to only use discrete graphics. Interestingly enough I also saw this affect Windows 10 occasionally.
Downgrading dock to 3.1.64 resolved the issue (although that firmware has issues of its own).
12-30-2019 02:55 PM