Ok, so I have tried 2 different cards in my HTPC and cannot control GPU voltage on either card, so I am beginning to wonder if my MB wont allow GPU voltage adjustments. Specs: P8H61-I R.2.0 with an I3 2125, 8GB Corsair 1600 Ram, And an MSI TF3 Non OC 7850, all running on a Silverstone 450w PSU. I tried to unlock voltage on a 7770 as well and thought that maybe it was the card, but now 2 cards in a row has me wondering if it is my board. I have tried drivers all the way from 12.6 to the most current 12.11, Tried afterburner 2.2 , 2.3, 2.5 , With the EULA and without, I make sure to check unlock voltage. The voltage block is just blank and the slider is all the way to the left. I have tried Trixx , and GPU Tweak. No voltage in either of those. I am stumped and feel that it must be my motherboard holding me back from a good overclock. Please anyone with advice chime in.