My nic card cant recognize new ip address

Hey guys, for some reason my nic card isnt recognizing the ip address when i get off the router and connect to the modem. I was told on another forum that this is becuase im using the wrong ethernet cable. If this is true what cable should i use so that my nic card can recognize the ip address instead of keeping the router ip address which is 192.165.2.100.

please help if possible, thanks in advance

I don't think its a cable problem did you try static ip if you are behind the router static ip's are much more better than dynamic in such situation if you are saying you need to connect a router to a pc than you would need a cross cable if it goes to a switch you need a straight.

Try static ip it might help sloving your problem

And if you are connecting your modem to your PC you will need to use a straight cable maybe you aren't grabbing an ip as previously with your router connected you were using a cross cable

Straight cable: Devices of different familes
Cross cableevices of the same families

thanks, i a different cable and it work, but im not sure how to tell the difference between a cross over or straight cable, i was fortunate to that i found a cable that works.