I also face the problem.I solved this via "Additional Drivers" tab in "Software&update". Here already selected "Do not use the device"
Now u select " Using 802.11 Linux STA wireless driver source from bcmwl-kernel-source(proprietary)" click "Apply changes"
Dell Wireless 1704 Linux Driver For Mac
DOWNLOAD
https://urlin.us/2wITkP
Screw Dell for not picking a wireless chip with an opensource driver or at least a driver that can be safely assumed to stay current with kernel releases rather than stagnating on the kernel version the laptop was shipped with
I have been using b43 for a few months. It has a lousy signal strength compared to broadcom-wl (in my Ubuntu installation). I discovered twelveeighty's package today and i hoped i could make Archlinux have the same wireless range, but no game up to now.
This may become a multistep problem depending on what the issue is, since you've specified your wireless card have you tried googling around for "Dell wireless 1704 arch linux"? the first link that comes up is here seems to have a solution if you're lacking the driver.
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