In our first overclocking session, we were able to take the card upto 750/1800/1134MHz, which is not bad, but far from good enough to play a role in the top of the 9500GT overclocking rankings over at Hwbot. So, we were in need of extra voltage to be able to increase the frequencies without the card getting unstable.Before we present you the voltage modifications of the Galaxy OC 9500GT, we want to stress that Madshrimps is not responsible for your actions. If you want to modify the videocard, please know what you're doing!
Check out our soldering guide for some useful tips!
First, the voltage modification for the GPU core:
To increase the voltage, solder a 50k ohm variable resistor between the red and green dot. In this case, the red dot on the voltage controller (Nexsem 2423DS
(PDF)) the FB pin. However, please use the alternative soldering point which is also marked by a red dot. The green dot is a soldering point to ground. You can either use this point or any other ground on the card.
Second, the voltage modification for the memory:
Again, you have to solder a 50k ohm variable resistor between FB (red) and ground (green). For reference, here's the PDF file of the voltage controller: Richtek 9259A
Last, the voltage measurement points:
Red dot: Vgpu measurement point
Green dot: Vmem measurement point