Upgraded to Windows 10, both ethernet and wifi do no work. They seemingly connect to LAN, but not to WAN.
Updated to win 10 64 bit drivers on dell website, still didn't work. Rolled back, still didn't work. Rolled back Windows 10 back to 8.1, and reinstalled 8.1 drivers, still didn't work.
Had to completely reformat computer to get network connectivity back. Not upgrading to Windows 10 until Dell figures out why their drivers don't work.