VDDCI

What the VDDCI VRM feeds on an AMD GPU is debatable, and something that this article would not touch on. The modification itself should pose no special challenge.

VDDCI1 AMD Radeon HD 6870 Voltage Modifications   The Complete Collection
VDDCI2 AMD Radeon HD 6870 Voltage Modifications   The Complete Collection
The default VDDCI voltage is approximately 1210 mV.
Again, ensure that the potentiometer is set to its maximal resistance prior to installation. You may wish to use a higher value potentiometer for less initial VDDCI gain upon installation.
No over-current or over-voltage trip points were observed below 1500 mV.