How can you reach this insane temperature except in living in the Sahara ? My cards, some R9 380, run at 49C at stock clock. My fans are at about 70% I think, but I'm not sure, since it varies automatically according to the card temperature. Mine are newer, so this might explain, but running the card at a so high temperature is not healthy for it I think.
The R9 380 is more efficient than the 7970. But the OP's 7970 is too hot. That might be due to bad ventilation.