Linux: Slow wifi with Intel and iwl3945

I have this lovely Thinkpad T60 on which I replaced the Atheros Wifi card for an Intel one a few years ago. I'm using Fedora 20 on it and noticed the wifi connection, although negociated to 54Mbps wouldn't get any better actual speed than 1 Mbps. I was on the edge of getting an Atheros back but here's what I did to fix the problem:

As root, add a new file:

/etc/modprobe.d/iwl3945.conf

With content:

options iwl3945 disable_hw_scan=0

then:

modprobe -r iwl3945 

modprobe iwl3945

No need to restart, the changes were instantaneous.

I don't know if it also helped, but prior to that I had removed NetworkManager and installed wicd instead. Look around on how to do this if the above solution alone didn't work. One thing though if you install wicd-gtk, I had to add my user to the "users" group and then reboot. This had nothing to do with the problem. I reinstalled NetworkManager and everything was still fine.

All thanks to this comment on ubuntu launchpad. It's from 2011 but still works.