Not sure but I know it's less than the 2 6970's I got in another rig mining 24/7. I don't worry about electricity as long as I make enough in bitcoin to cover the overhead. My electric bill for my entire house with central air running when I'm home, 2 PC's and a TV is around $250 a mo and I make roughly $350+ (well at least before the recent price drop think I may hold onto my coins till they get back up above 13) so wasn't a big concern. I may move my 6970 rig to my friends garage who has free electricity but I didn't want to share my profits but if the price stays low under 10 It may be better.