The GeForce RTX 3060 Ti reportedly uses the GA104-200, a cut-down version of the RTX 3070. Rumored specifications say the RTX 3060 Ti has 4864 CUDA cores, 152 Tensor cores, 38 RT cores, 8GB GDDR6 memory clocked at 14Gbps, a 256-bit memory bus, and a TDP "somewhere around 180W and 200W".
The figures provided by our sources are all above NVIDIA reference specs, however, by comparing them to what we already know from NVIDIA, we could assume that the reference TDP specs for RTX 3060 Ti are somewhere around 180W to 200W (factory OC models). A custom board requires a single 8-pin power connector, it is safe to assume that the reference board also requires such a connector.