At 25 eurocent per KwH, its barely going to be cost effective, even if your computer is already on anyway. When just browsing or doing nothing, your videocard will consume something like 30W, if that. While mining bitcoins it will be close to its TDP, dont know the numbers by heart for your card, but probably 160+W. So you would add ~130W for ~370 MH/s
Use those numbers here:
http://bitcoinx.com/profit/index.phpI think it comes out pretty much break even.
That said, I
second third the bitminter suggestion. Bitcoinplus is total waste of time and energy, its CPU based.