You can calculate how much you'll earn a day "solo" mining with your graphic cards via a difficulty calculator. (Search up "Bitcoin mining difficulty calculator on your preferred search engine). It won't be much, if anything at all. If you want to get into mining, I would suggest a dedicated mining device, specifically made for mining. Since, you'll be degrading your valuable GPUs at a much faster rate than with a dedicated mining device, since they factor in the load that mining requires, whereas gpus don't usually do so.