GPU Voltage Mod - Pencil Method

This very simple pencil mod was originally created by Lord Anselhem. The advantage of this mod is you don't need to do any soldering on your Radeon 9800 Pro!

All you need to do is simply connect pin 18 with pin 20 of the SC1175CSW voltage controller chip by drawing a line using a pencil.

SC1175CSW voltage controller's pin configuration.
Extracted from the SC1175CSW datasheet.

You will need

• A sharpened pencil (preferably 2B or 4B)
• A multimeter (preferably a digital model, with an accuracy of two decimal places)
• A magnifying glass (if necessary)

Before you actually start to mod, you should measure the default voltage of your card first. Locate the area outlined in the picture below.

That's where you will need to measure the GPU's voltage. Remember, you will need to do this with your system turned on.

Let's take a closer look at that area. See the two labeled points? To measure the GPU voltage, you need to connect your multimeter's positive point to either point A or point B; and connect the negative point to a ground point.

You can either use your computer case or the Molex power connector's ground wire as the ground point. I personally prefer the Molex connector's ground wire because I can just poke the multimeter's negative point into the Molex connector and leave it there.

The GPU's voltage will usually be around 1.6V to 1.7V. But you must find out your card's exact GPU voltage before you mod it.