Absolutely not slower unless you have bad issue with PC or driver. I upgraded from 2x980SLI to one 1080. Have not missed SLI once. it is a bit faster than the SLI 980, so it will be A LOT faster than one 970 without doubt.I hope so. Just read a review saying how there 1080 is slower than there 970 which I find hard to believe must be a problem card wise ��