First off, I know Dell computers extremely well because I use them exclusively at work and frequently have to troubleshoot and repair them for my job. That's why I chose to buy a refurbished Dell -- even if it's got problems I know how to fix them. However, even after using every troubleshooting effort known using different monitors, cables, Dell docks etc. I still have no video output from the USB C thunderbolt ports nor the dedicated HDMI port. I have tried every driver old and new, updated all possible updates, did all the YouTube and Dell troubleshooting tips, even upgraded to windows 11 pro and downgraded again.  After finally doing a factory reset with no results I give up. Everything else seems to work fine, and the case is minorly beat up.Laptop with external monitor capability is useless to me. Returned.***UPDATE*** I'm adding two stars back because the customer service was prompt to handle the issue and process the return.