You won't get much bud at all. What's your setup like? 12/12 with cfls I'm gonna guess and say a couple grams dry. My very first auto I grew at 12/12 with my photos under 1000w hps got me less than 3 grams.
it is worth noting that I knew nothing of autos at the time, used way to big of a pot, she was a little far from the light as my photos were much taller. Regardless tho autos under 12/12 don't produce much.