I'll give you 700 btc when they are generated if you send me the card now.. lol
It ain't magic, at current difficulties you are most likely never going to reach that in an acceptable time and the difficulty increases will make this task even harder.
If the difficulty increase becomes linear and BTC price doesn't decrease, then I think a card can generate its money.
But it will take months. And you need a good GPU.
And you'll have to take into account the cost of electricity too.