Thank you Voithos for your quick response.
Unfortunately, this is a more fundamental bug, therefore none of the solutions you offered is going to solve this.
This is a brand P1 Gen3 laptop with all the latest updates. This is also not an issue that can be fixed with an OS setting...

I believe this is not really a docking station issue, I believe the same bug happens when connecting the laptop via HDMI, although I never confirmed.

I am looking for more professional assistance here, maybe @someotherguy could assist as he did great with the latest "System Update 100% CPU" bug in a different thread (I had the same bug and the latest update fixed it)

Keep in mind that I know other people with the same laptop are experiencing the same issue.

I'm willing to share any logs before/after the issue happens to help you debug, just let me know what exactly you need.

Thank you

I kept digging and came across a different thread on the X series forums where people mention the exact same issue, even P1 owners replied there...

This seems to be an issue with the integrated graphics drivers of Intel... When switching monitors there's an issue between the discrete graphics and integrated graphics...

I confirm that disabling and re-enabling the Intel Graphics drivers provides a workaround that fixes the problem...

Could you please investigate this further and fix this?

The full conversation here: https://forums.lenovo.com/t5/ThinkPad-X-Series-Laptops/X1-extreme-screen-lag-on-quot-second-screen-only-quot/m-p/4475674?page=6#4561850

In that thread, it was mentioned that this issue was fixed in version Intel Drivers version 27.20.100.8587, but this is before the initial release of P1 Gen3 Intel drivers...

up

@Serene_Lenovo @Andy_Lenovo maybe you know anything?

Is there any official place I can report this bug other than this forum?

Hello,

Considering the P1 Gen 3 and X1E Gen 3 share the same BIOS, Chipset and graphics drivers I would expect to be seeing more reports concerning this issue on both Gen 3 systems and the thread you point to is from before the Gen 3 was released and is therefore not really relevant to the system currently in question. You also don't state exactly which docking station you are using, nor which cables and how the devices are connected which could also be important factors.

If you wish to create an official bug report you need to call support and open a case. 

Thank you Andy.

I mentioned in one of the replies that this was actually not related to the docking station itself, but to the situation where a monitor is connected/disconnected.

This is not a specific monitor issue, nor a cable issue as I am experiencing this with different types of monitors and cables. And my team mates experience the same with different setups.

I'm not saying the post I was referring to is the exact same problem, but it shares similar characteristics.

But you missed my main point - disabling and enabling the Intel Graphics drivers fixes this, so this is definitely related to the the integrated/discrete graphics switching process.

For whoever reading this thread and experiencing the same issue.

I opened a ticket today and since I'm eligible for premiere support the tech team responded to me very quickly.

I was told this is a known issue for P1 and other laptops, the current solution offered by Lenovo is to switch the setting in BIOS for the graphics card to "Discrete", this will disable the integrated Intel graphics card and will solve the issue.

Although this is not a perfect solution, I understand that Lenovo can't fix this without Intel's assistance.

Even if it feels like I'm a bit late, I just discovered a similar problem with Intel-Nvidia combination on my Laptop and may help you here.

First of all, the blurryish windows are part of Windows itself, rightclick on the app you wish to "de-blurr" and on settings play around with compatibility as "high DPI settings" and disable full-screen optimization (im sorry, my windows german, so my translations may vary from your experience). Worked like a charm for all of my blurry windows yet.

Now the tricky part. I experienced some simliar occasions without a dock, so this may not help, but its worth a try. I figured that it has mainly to do with power consumption and that is, that the CPU has a turboboost that consumes more power than lenovo would assign to the CPU resulting in the GPU lacking of maximum power due to the physical power limit. If anything you have, feels like this, there is a chance. ( Btw, get rid of the autostarted "Lenovo Display Optimizer", I dont know why, but this also caused my mouse to lagg )

The key tool is the Intel's original Intel(R) Extreme Tuning Utility. Sounds gross, we won't use it for overclocking, but for underclocking. In its settings for the core, you will find the "Turbo Boost Short Power Max", mine is set on 51W on standard, while Lenovo seems to propose 47W at maximum. Long story short, I completely disabled Turbo Boost Short Power Max, and set my Turbo Boost Power Max on around 30W for testing - This may also vary for your Laptop, a too low value will immediatly cause your system to lagg a bit more, a too high value won't have impact. There are also videos around, explaining alot more than I can here. After I spent 2 month looking for it, my computer runs smooth as f*** now. I'm sorry if that doesn't help, but it looks like a note-worthy alternative to completely disabling integrated graphics - specially as there is no such option for my T15 I fear.