RE: Trouble with XPS 15 9550, USB-C/Thunderbolt 3, and external monitors
Dell XPS 15 9550 A10 System BIOS
Still busted for me after this update. With USB-C to mini-DP adaptor going to a 4K monitor, it disconnected when I searched for Wi-Fi networks - when I have the Wi-Fi adaptor set to 100% power output.
Also for some reason now the 5GHz 802.11ac network I usually connect to is only connecting at 54mbps regardless of the power output setting I choose - not sure if related to the BIOS update.
I give dell an F.