i went to this site :
http://bitcoinx.com/profit/index.php?hashrate=314&cost=300&electricity=0.25&power=150&months=3.0000&decline=0.50&blockcoins=0
and calculated your profits with an overclocked ATI Radeon 5850, german electricity costs and without counting in the additional Hardware.
You will generate 0.1172 BTC Coins per 24h at these conditions.
These will net you ~ 3.3 BTC per Month.
Power cost per 24h: 0.90 USD
Revenue per day: 1.29 USD
Calculations as per Today's difficulty which will go up and Today's price which varies.
So it is not that profitable.
In the next Months your revenue will decrease by a large percentage when specialized Asic Mining Chips will hit the Market.
damn son, laying it down