Some leaked (censored) slides from OBR,
All it tells us is that the clock speed is below 1000MHz, the Cuda Core count is 4 digits (above 999) and that there is no hot clock, as rumoured. So those Lensfire specs are no even more obviously wrong. The other, stating 4096 cuda cores may be correct, but I'm expecting less cores myself.
Also, it (i'm assuming GTX 680) is faster than 7970, on internal benchmarks. As expected. How much? No idea.
EDIT: NVM... it's probably fake