I've previously reported a solution by updating drivers on the intel wireless card. after dell performed this update things ran very well. for a few hours, then back to poor reception for download. dell has decided, after replacing the wireless card twice, and the display assembly once, to now send me a replacement unit. I will test this before transferring all my stuff and provide a report.
but here's something interesting:
when I disconnected all of my USB devices the wireless started really working well! We checked settings on power sharing, but were unable to effect a change that worked. in particular, my powered 4-port USB 3.0 hub seemed to cause the most problems.
Perhaps this issue goes to the power available to the wifi, which may account for the extreme proximity impact. I can report the same symptoms as most others. after a few paces distance the signal falls off rapidly - inverse square and all that.
Another interesting thing:
The system, with dell's assist online, was unable to stop the onboard wireless from connecting while using the external dongle. all setting were overridden and the onboard wifi persisted in connecting despite settings to not automatically connect.
So I think the problem is that there are too many necks to choke in the building of this unit. Intel, Dell, and other sub-system suppliers each provide items that meet required specs, but together they just step all over each other. Way too many variables here. And no one is clearly accountable. Except, of course, Dell. but I think their process is in over its head here. The level of system and engineering control is insufficient to eliminate the risks that something like this will occur; and the resolution is more complex after the fact than before release.