Limiting the broadcast to N only killed my connection. I will tinker a bit more to see if perhaps it is a security authentication problem, but I did check the key settings and they match.
Adapter: Intel WiFi Link 5100 AGN (So yes, Intel chipset... onboard chip in Dell Latitude XT2)
DIR-655 = Hardware version A4 Firmware revision: 1.32 NA
Another oddity. When this machine is connected to my wi-fi network at work Windows tells me the "Radio-type" on the connection is 802.11gn but currently it shows up (at home) as 802.11n, even though my router says I'm connected as g . Still puzzled here....