I have been using cat6 cable on all the new pulls of cable, but I didn't realize I had a section of cat5 cable from the second computer. I thought it was slow, but I did an iperf test, and it showed the throughput was only 100 mbps. I changed the cable and it's up to 1000. Amazing. This becomes important when you get a 4K tv. Also, we are getting direct fiber soon, and everything should be up to the gigabit.