for nvidia gpus to predict performance of new gen its always been like
xx60 = somewhere between last gen xx70/ti
xx60 ti = last gen xx80
xx70 = last gen xx80ti
xx80 = cant predict this one maybe some where from 30 to 60 percent faster compared to last gen xx80
xx80ti = 50 to 80 percent faster compared to last gen xx80ti
only one case where it differed was when there was huge node change from 28nm to 16nm/14nm architechture that was i guess maxwell/pascal era