- Are you sure that you refer to an IBM gen 2 type c thinkpad docking station and not a Lenovo ThinkPad USB-C Dock Gen 2 docking station?
- Are you sure that you refer to Lenovo ThinkPad 14s and not a ThinkPad T14s Gen1, ThinkPad T14s Gen2, ThinkPad P14s Gen1, ThinkPad P14s Gen2, ThinkBook 14s Yoga, nor ThinkBook 14s?
- Have you already looked into the manuals of your laptop and your docking station for further details, constraints and system requirements?
- Have you already looked onto Lenovos support site for your device models for firmware AND driver updates?
I couldn't find neither an IBM gen 2 type c thinkpad docking station nor a ThinkPad 14s existing. So I don't know your models, your CPU nor your GPUs. There exist models with an optional dedicated GPU for the notebook.
I have 3 monitors connected to the dock.
- So you try to operate 4 displays, 3 external ones and the builtin internal one, and you had success but only encountered limitations of resolution for the 4th display?
I have updated the docking station and my laptop is up to date driver wise.
- How do you know that your drivers are up to date? Why did you not update also your firmwares of laptop and dock?
According to a note of a user on the Lenovo user forum
, the Lenovo support could help by directing the user to the support web site with the drivers AND firmwares, together with the hint that the usual update tools will not detect all available updates, hence requiring manual updates. On the same forum, there other hints which have helped some users with different notebooks and probably same docking station to uninstall a driver and other steps including power cycles. The Spiceworks field guide for pos(t)ing good questions including its helpful references
found at the bottom of its web page reminded you to search first for the answers to your question and report what you have already tried and where you get blocked. I couldn't find such details in your post. You may need to scroll down to find these helpful references.
Any monitor i use as monitor 3 has the limited res issue. any ideas?
Yes, plenty. Please follow the field guides recommendation to first search the answers yourself. Then look into the infos you found. I already mentioned some. I'm not able to become more specific as long as you don't disclose your models.
Here is a display support matrix
from the Lenovo support web site as mentioned in the afore mentioned Lenovo user support forum topic.
As you may have read in the afore mentioned Lenovo user forum, you should know that the number of supported external displays depends on several factors:
- Are you using a notebook model specified to only support 2 external displays while the builtin display is in use, like the Lenovo ThinPad T14s Gen1 (Jazz 2) or ThinkPad P14s (Drift 2) with 2020 Intel CML and using video signals configured to DisplayPort 1.2 with the 2020 or 2021 notebook models and the Thunderbolt 4 docking station?
- Or are you using a Lenovo ThinkPad T14s (Gen 2) or ThinkPad P14s (Gen 2) with an Intel CPU which should then support your 4 displays including the builtin one of your notebook when your docking station is a Lenovo ThinkPad Universal USB-C (40AY) with the correct power supply?
The Lenovo support web site already reports that the number of supported displays depends on the GPUs used, builtin in the CPU or dedicated, the link used for connecting the dock, the dock model, the configured display resolutions, the configured DisplayPort signal. The Lenovo user support forum mentions in addition dependency on the power supply of the docking station. It also mentions that 3rd party Universal USB-C docking stations with 90 W power supply may have slightly less dependencies. And you may also have more luck if you reduce the number od displays from 4 to 3 by disabling the builtin display when connected to the docking station. It also mentions that you may need to power off and on notebook and docking station after a configuration change as these might have difficulties applying these changes. without a cycle of powering off and on. It also mentions difficulties when using a Lenovo 65 W instead of Lenovo 90 W power supply for the docking station.
So as you have learned that applying the Spiceworks field guide has revealed that some more context info is relevant to answer your question and you would have found the answers specific to your incompletely disclosed situation.