Do not know if this has been solved yet but I have a T420 and the wireless cards are usually either intel or Arethos, intel pro 4000 (or something like that) was mine, and I had to download it from Intel, NOT Lenovo (would not work from Lenovo)... Seems to be common for Lenovo, because I have 2 and neither Windows or Lenovo would work had to get em direct from the manufacturer website..this will require you to know what kind of wireless card you have in it though... According to Windows my G780 had an Arethos card, but it would only work on 2.4 Ghtz, after uninstalling and installing a Broadcomm Wireless driver WOW I had 5Ghtz as well
Mod Edit: OP last active date of original topic - Hamluis.
Edited by hamluis, 06 May 2018 - 08:21 AM.