Network issues with lan and wifi

[Guido Martínez <mtzguido@gmail.com>]

Hi all,

I recently purchased a 802.11n wifi pci card and placed it my pc.
After that, I proceeded to install debian. I noted that I could not
configure the wifi network from the installer (it's probably possible,
but I don't know how) so I attached a network cable and the
installation ran smoothly.
Now I'm booting into debian, with the cable still connected since I
have no network manager for wifi, and the connection is crappy. It's
not a hardware or internet problem since this same PC in windows has
no issues, as the other PC's in my house.

Now I removed the wifi card and the network runs with no problems.
What could be causing this? I'll provide info if you need any

Thanks!