Posted 28 February 2010 - 08:31 PM
802.11n routers aren't always everything they are cracked up to be, and a lot of the advantage doesn't apply unless you have 802.11n adapters on the clients. It is quite possible that your older G router had better antennas, and possibly more power, than the brand spanky new N job.
That said, if your router has a site survey option try it out and make sure you are set to channel 1, 6, or 11, whichever has the weakest competing signal. If it doesn't, try downloading NetStumbler (for Windows) or similar (iStumbler for Mac, for instance). Then unplug your router and walk around your place with the Stumbler running on your laptop, if you have one. If it's just desktops then that will do. What you are looking for is the signals on channels 1,6, and 11 that are weakest everywhere in the areas you use your computer. That's the channel you want to use for your router. You can also look for "loud" signals on the off channels as well, and avoid them if you can (i.e. if there is a strong channel on 2 or 3 avoid channel 1, channels 4,5,7, or 8 avoid 6, and 9 or 10 avoid 11). It is better to be on the same channel as another strong signal than be off by one or two channels. If two SSID's use the same channel they will contend for air time, but if they are only one or two channels apart they will see each other as pure interference.
Stuck at renewing IP can also indicate that the WPA or WPA2 authentication did not go well. Double check the settings on all parties, or try turning off encryption temporarily to check things out. Also, you may have to delete (or disconnect) the old wireless connection then establish a new one, particularly if the security settings changed.