Also try unplugging the router for 20 sec or so to reset. Make sure your card is seated all they way into the slot. I noticed you said the MoBo didnt fit very good, so look down the length of your card in the slot w/flashlight and verify its seated good. Also you did remember to install drivers & software with card out. then install card. Ground yourself from ESD.
Also this may or may not be a viable leed but, did you change PSU or are you using the older gateway that was in there. You might hook up a tester to verify correct power and stability.
-J