Hi AchimR12,
Welcome to Microsoft Community and appreciate your time taken for sharing detailed information. I understand that AMD eGPU on Windows 11 - external graphics does not show up in Device Manager. I am glad to offer you help on this issue.
You first need to determine whether your hardware devices match before you can make software adjustments. If your hardware doesn't match, it's true that a cable could be plugged in but won't work. And for Thunderbolt, we need download the driver. You could download it from the official website.
And check the Thunderbolt option in BIOS:
Press F2 during boot to enter BIOS Setup.
Go to Advanced > Devices > Onboard Devices.
Check that the Thunderbolt Controller is enabled.
Press F10 to save and exit BIOS Setup.
Use a certified Thunderbolt™ 4 cable. The length of the cable could also be a factor. Try one that's 60 cm or shorter.
Your external graphics card isn't recognized. This problem can appear if the video card is not installed properly in the PCI slot and as a result the card is not detected in device manager. Check the physical connections again, reinsert the card properly in the PCI slot and then install the drivers from the manufacturer’s website.
After entering the system, we right-click “This computer”-“Manage”-- “Device Manager”, find the option with “PCI-e” meaning to try to disable one by one, until You see your laptop’s separate graphics options disappear. Different computers have different options and you can only try them one at a time.
Turn off the laptop - turn on the independent power switch and start the external video card - start the laptop. At this point, we can wait a moment to find that the external video card has been identified in "Device Manager", but cannot be used because there is no driver.
Next we download the corresponding video card driver and install.
If the video card is installed properly in Video card but still the problem persists, let’s try these methods below and check if that solves the problem.
Method 1
This fixit checks if the device is currently disabled or turned off or the driver is not installed.
Hardware devices are not working or are not detected in Windows.
Microsoft Easy Fix solutions have been discontinued
Method 2
Sometimes, some devices in device manager are hidden due to corrupt or missing drivers.
Follow the steps below to show hidden devices in the device manager and troubleshoot accordingly.
Press the Windows key + X
Select Command Prompt (Admin)
Type set devmgr_show_nonpresent_devices=1 and hit enter
Type Start DEVMGMT.MSC and hit enter.
Once in Device Manager hit the View menu and select show hidden devices.
Method 3
If methods suggested above does not help, I would recommend you to contact Lenovo X13 Gen2 to get chipset, BIOS, graphics card, drivers installed properly.
I hope the information provided is useful for you. If you have any additional questions, please do not hesitate to reach out to our support.
Best Regard,
Kevin | Microsoft Community Support Specialist
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