Update = After verifying ownership and completing troubleshooting, a DELL-Cares agent setup a like for like system exchange.
I received my XPS 8940 on Friday July 9. The minute I plugged it in, the fan started to run quite loudly. I immediately called support. The tech had me start the PC. The fan stopped.  He then took me thru the setup process. Later, when I shut down the PC, the fan came on again. I had to unplug the PC to make the fan stop running. The fan also comes on when the PC goes to sleep. I called support again the next day. The tech ran me thru diagnostics and concluded he couldn’t fix the problem remotely.  Is anyone else having a problem with the fan? Can it be fixed or should I ask for a replacement?
XPS 8940, loud fan issue