@Dellbodhi Happy to help! If you haven't already, try setting your XPS 15's internal display to 200% scaling. A 4K display at 200% scaling gives you the equivalent size of a 1080p workspace, and most people find 1080p on a 15" laptop display to be usable. But 4K at 300% scaling only gives you a 1280x720 workspace, which isn't much to work with by today's standards. In terms of the T480, the ThinkPad T480 comes standard with Thunderbolt 3, so it should work just fine. But if it's not working, can you be more specific about what exactly is going on rather than just saying "it won't work"? Does the dock even provide power to the T480 when it's connected? That should work even if nothing related to Thunderbolt data transmission works, but if even power isn't provided, then there might be an issue with the port on the T480 itself. If you can get power, do you have the Thunderbolt software installed on your system? Are the BIOS and Thunderbolt 3 firmware both up to date on that system? Did you make sure that Thunderbolt is actually enabled within the BIOS since sometimes it gets disabled due to security concerns? The default Thunderbolt security level in the BIOS should be User Authorization, and in that case when plugging in the WD19TB for the first time, if you have the Thunderbolt software installed, you'll see a popup requiring you to authorize the device. If you choose "Always allow" there, then you won't have to do that going forward. And just to confirm, you're connecting the T480 using the cable permanently attached to the dock, correct? If you're trying to connect it to the dock by plugging a TB3 cable into the "downstream" TB3 port at the back of the dock to try to have both your XPS and T480 connected simultaneously, that isn't going to work.