Is this an AMD/Intel hybrid rig?
If so try the drivers from Lenovo for both GPUs
It is an intel HD 4400 - and I downloaded and installed the latest driver from the lenovo website.... no HDMI output
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In that case, I strongly recommend contacting Lenovo and see if they have a set up in the BIOS or different configuration that might be required, other than that, most likely it will be a defective HDMI port.
You can get support here:
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