SMC Barrier Router

I have a SMC 4 port barrier router. I can not get my nic cards can not xmit at 100mps.
SMC has been no help. I have set up nic card at full duplex. But I do have a lexmark printnshare device and it will xmit at 100 mps.. the nic cards I have are 10/100 autosensensing.. please help