Man of Honour
Nvidia's GTX 1070 Ti is expected to use 9Gbps memory
https://www.overclock3d.net/news/gpu_displays/nvidia_s_gtx_1070_ti_is_expected_to_use_9gbps_memory/1
It seem 1070 Ti spec is not final. 9Gbps GDDR5 would see 1070 Ti have 288GB bandwidth compared to 1070 256GB bandwidth on slower 8Gbps GDDR5 memory.
The rumoured specs look made up anyway.
If the 1070 Ti has the same base clock as the 1080 it should also have the same boost clock.