Cheers I thought 850 should be okay but was just checking, I did go on a few psu calculator websites and they put some doubt in my mind with a range of results some with a 200 watt difference! I'll probably go with the EVGA G2, 10 year warranty is insane which shows there confidence in the product. Oh and on a side note the psu calculator on the corsair website has the 980Ti in the gpu list! hmmm interesting