Mining Bitcoin will rarely be profitable. I would recommend mining altcoins that you think will be popular and selling them for BTC once they do. I got $80 in BTC for my 6 hours of Dogecoin mining with a mediocre CPU before it got big. Imagine what I could have gotten if I mined it for a week with a GPU!
Listen to this guy, very smart thing to do.
Invest small and probably now upgrading that gpu to some other stuff to build a better alt rig.
Also chose a good ALT coin, since the algorithm of that coin is different then all the other ones.