Wireless networking was always a bit patchy for me on my Dell Latitude D630 while running Ubuntu Gutsy version of Linux. It would work fine for ages and then freeze up suddenly, requiring a hard reboot to get things working (Apache would become unkillable, I guess because it was attached to the broken Wireless networking driver.) Problems always showed up when I transferred large amounts of data between Linux and my Macbook. Files copied fine for a few minutes and then the whole house of cards would collapse. Crash! Boom!
The first time I looked for a solution nothing turned up, but eventually I went searching again, and after digging into all sorts of forums and websites I found the simpe solution on the Dell Linux Wiki:
Create a file called /etc/modprobe.d/blacklist-ipw3945 and add:
Add to /etc/modules:
Reboot after doing that and all will be fine in the world again! I haven’t had any networking issues since replacing the ipw3945 driver with the iwl3945 one!