Vr-Zone did a voltage mod on the XpertVision 7600GT Sonic graphics card:
The XpertVision 7600GT Sonic we reviewed just a short while ago is one of the most unique 7600GT in the market, not just because of it's higher than reference clock speeds, but more so because it is one of the very few 7600GT not based on a reference PCB design.
Since it uses a different layout, our voltage modification guide based on the reference design we published a while ago will not apply for this card. However, modifying this card is as easy as it gets. It can be as easy as a pencil job.