Hi I have a 2851 router and I would like to upgrade my T1 to T3. I was told that NM-1T3/E3 T3 card will work with the 2851 router but not to the fullest capability because this router does not support this kinds of speed. I have a 3600 router that does support this card but this router is not used since it was replaced with the 2851. I just thought that since the 2851 is newer it should work since 3600 is an older router. I just want to confirm with an expert on how much capability (speed) will be sacrificed with the NM-1T3/E3 card. Any help is greatly appriciated. Thanks