Witch,
You got networking wrong buddy
This is very simplified, but think of the wire coming out of your computer or miner as the TALK line. You can't plug a talk into a talk. Then everyone is talking. (Again, this isn't exactly true, it's a multi-duplex line of course, but the principle applies). No one is listening.
You need a router to listen and relay the message, or you need a Crossover cable instead of a Patch cable (you have a patch, as do 99.9999%).
Assuming you have a router, plug one cable from the antminer to the router, then one from the computer to the router. Set your IP to 192.168.1.90, sub 255.255.255.0, and gateway to 192.168.1.1.
Then just open a browser to 192.168.1.99 and there she'll be