According to the latest leaks, rumors and information provided to wccftech the GeForce GTX 1170 is powered by a 104 class GPU, codenamed GT104 that measures around ~400mm². The GTX 1170 would have around 2688 CUDA cores, a 256-bit GDDR6 memory interface and 8 to 16 gigabytes of 12Gbps GDDR6 memory, which is slightly slower memory than the GTX 1180. The graphics card is expected to have a core clock of around ~1.5GHz and a boost clock of around ~1.8GHz. The TDP of this graphics card is unconfirmed to date, but is expected to be somewhere between 140-160W.
Would put in the range of a 1080ti....which would be impressive.
Take with a grain of salt but gives a rough idea of where 1170 and 1180 would be: