@ Kronos
thank you. So it should be some version of 7457 ( probably the last, the same I have, 1267 MHz ) and modded VCore, which is unknown for me.
Because this Sonnets are rare, I thinked you did CPU swap and play with overclocking and VCore. My mistake.

Fortunatelly I have nearly all necessary info from macrumors, last piece I missing is exact increased VCore for 1.8 GHz. So I will try 1.75 GHz + some calculated VCore value.