Re: AMD64 + N300 USB adapter
You could have installed a pae linux-image as i did:
I was running ubuntu 11.10 32 bit until I discovered that it didnt use all of my RAM (only 2 gigabytes were in use out of 8 gigabytes) so I switched to AMD64.
If the fix above doesn't help, you might try these attached. You'd need to remove bcmwlhigh5 and install bcmn43xx64.inf.
chili@LAPTOP60:~$ uname -r
chili@LAPTOP60:~$ cat /proc/meminfo
MemTotal: 3914860 kB
MemFree: 1507120 kB
Buffers: 264932 kB
Cached: 1545556 kB
"Oh, Ubuntu, you are my favorite Linux-based operating system" --Dr. Sheldon Cooper, Ph.D.