04-19-2018 03:57 AM
I have this issue as well. I have two monitors connected via DP/VGA to my P51 docking station.
I close the lid at the end of the day and eject, system goes into hibernation. When I pop it back on the docking station the next morning I sometimes get video on VGA, the DP never works. I then eject my laptop and reinsert to fix this issue.
I also changed to discrete in the BIOS, it did not help. Today neither VGA/DP works, and ejecting/rebooting doesn't fix the issue. I'm updating display drivers and the BIOS currently.
04-24-2018 12:48 AM
After months without reaction i worked out the following procedure which works stable for me to start up the hibernated laptop for the dock:
1) put into dock with closed lid
2) switch on using docking station power button
3) wait a short time, then enter bios password "blind" (screens are black, lid is closed)
4) wait until i see that keyboard and mouse led are lighted
wait a little more to be sure windows processes are ready and login would be shown (still all screens are black)
5) open lid - its black, you just see its background is lightly enlighted (so its "on")
6) eject running laptop from dock
now the login shows up on the laptop display after short flashing
7) insert laptop again with opened lid and login shown on laptop screen
now the main display also shows the login and i can log in
8) close the lid and start working...
not nice and normally not acceptable for a machine in this price range, but i am sure its a software not a hardware problem so i did not bother lenovo again to exchange the motherboard. miniDP still not working.
i never got a reponse for my question to at least check the documentation. if it won't say my config should work, it would be a different story at least.
i am still hoping for a future update fixing my issue finally.
05-01-2018 11:04 PM
and here comes some good news.
after the latest updates suggested by Lenovo System Update (installed on Apr 23rd) which were BIOS, Intel Management Engine, Hotkeys, NVIDIA Graphics drivers and Intel Network drivers, plus a huge Windows 10 update, it now behaves in and out of dock as expected, especially waking up from hibernation works now as it should - only minor issue is i still have to enter the bios password "blind". But i get directly the logon screen without all the annoying steps described above.
Only thing i noticed two times now is when having an external monitor attached by HDMI, keyboard "freezes" as if the system has crashed. But taking the HDMI Monitor out keyboard comes back to life... Didn't check the miniDP so far.
08-10-2018 01:26 AM
If anyone is interested, here the latest update.
After installing Quality Update 2018-07 Win10 Version 1803 (KB4340917) startup is not working properly any more.
Now i have to insert (hibernated) laptop in docking station and open the lid. After entering password (what i see on the laptop screen of course) system wakes up, external monitors start working and laptop screen goes black. Can close it and start working.
When i do not open the lid, bios password entry from external keyboard is not accepted and system powers off after a short while - no i did not enter wrong password all the time during testing :-)
So it's not too bad compared to the beginning, but it looks like it's time again to wait for another update to get a working system...
11-26-2018 04:21 AM - edited 11-26-2018 04:25 AM
I read your post with interest.
I have a slightly different problem I'd like to share.
I have a P51 with a matching Lenovo Workstation Dock. I am using two Lenovo monitors additionally to the Laptop Screen. Windows tells me that the Intel graphig card is serving the Laptop Screen and the Nvidia is serving to the two monitors.
Our company a preinstalled set of device drivers which worked fine, which is for the Nvidia Quadro M1200 this Version: 18.104.22.16864 As soon as I updated the Nvidia drivers to anything newer the two monitors stay black. They are not going into power saving mode (the led stays green, not orange as if it is not connected) similar to what you described.
I couldn't resolve the system besides going back to the old drivers.
I do not have access to the BIOS and can not install Windows Updates (Im currently on Windows 1803, Buildnumber: 17134.112).
So thats my 5 cents. Maybe you want to try this specific driver version, I will follow the thread if you find any other solution.