PC can not receive an IP address while my router can

PC can not receive an IP address while my router can

Situation
Recently I changed my local network architecture a bit, because of which I
know connect directly to my modem with a UTP cable to my pc instead of
over wifi via a separate router. For some reason though my PC can't obtain
an IP address(it says it's connect to an "unidentified network"), if I
switch the ports on the modem for my router and my PC I have the same
problem, my router keeps working in both situations. Does anyone know what
could be the problem here? I'm at a loss.
Specs
Windows 8
Realtek network card
feel free to ask more stuff :)
EDIT: Some extra info, when I type ipconfig /renew in my command prompt I
get the following error: An error occurred while renewing interface
Ethernet : unable to contact your DHCP server. Request has timed out.