Dell support driver download ubuntu - really
I don't know what chipset (Atheros, Intel, etc) the wireless card has, but chances are the chipset is supported by Ubuntu out of the box. So when you install your new operating system, both adapters (wired ethernet and wireless) will be found.
Often it's easiest to run a long network cable to your router/hub during the installation of Linux. You almost always can get DHCP setup & running with little effort. as we all know getting your wireless up and running can be a bit more challenging - setting your ESSID, wep-key, etc.
So here's my recommendation. plug your laptop into a wired network during installation. Once the system is installed, make sure you can get out to the internet over your wired lan segment.
Then run "yum -y update" and go out for beer. It will probably take a while for all of the latest updates, patches, etc to download.
Once your system is installed & patched - then try to configure your wireless segment.
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