Looking for help increasing voltage on 4850 with RBE

[jaredpace]

I hear that 4850's will do 1.20v maximum with software. Normally they come at 1.158 max 3D voltage. Does anyone know if you can still get 1.20v via RBE on the 4850? If it's possible, could you show me which register values to change, please.

I would like to squeeze an extra 25-50mhz out of the core without trying a hardmod. Thank you.