If you want to connect NIC to NIC, you need a crossover cable, The order of the little wires in the CAT5 cable is different on a crossover.
For ethernet it is,
green/white
green
orange/white
blue
blue/white
orange
brown/white
brown
and it is the same at both ends.
For crossover it is that order at one end and
orange/white
orange
green/white
blue
blue/white
green
brown/white
brown
Make enough of these stupid things and it will stick in your head too
