XPS 17 Fan Operation with WD19TB Dock and External Monitor

@jemsurvey1  The Thunderbolt 3 chipset actually consumes a fair bit of power and therefore generates a fair bit of heat while it's active, which might explain why the fans run while the WD19TB is connected.  In terms of controlling the fans, you can try experimenting with the Power Mode slider that's exposed if you click the battery icon in the system tray, since lower power modes might keep things running quieter, but you'll obviously be sacrificing performance there (fyi though I would advise against moving the slider all the way to Best Performance even when plugged in, since that setting prevents your CPU from reducing its clock speed even when it has nothing to do, which will definitely keep your fans active).  But apart from that, I don't know of a way to control the fans in this system directly, especially if you're trying to reduce their operation, which might not be safe anyway.  In terms of monitoring, take a look at HWInfo64 and click the Sensors button when it launches.  That might be more info than you're looking for.  If so, there are tons of utilities out there that will show CPU and GPU speeds, temperatures, fan speeds etc. in various ways (system tray icons, floating tiles on your desktop, etc.)