v1 GeForce 6800 Ultra 512MB PCI E Voltage Mods

The 512Mb 6800 Ultra PCI Express cards have a different layout compared to the 6800 ultra 256Mb. As such, voltage modding them are a bit different. VR-Zone shows you how to voltage mod them for better overclocking!

The 512Mb 6800 Ultra PCI Express cards have a different layout
compared to the 6800 ultra 256Mb. As such, voltage modding them are a bit
different.

First let us check out the area of focus, all at the back of the card:

vmod3 GeForce 6800 Ultra 512MB PCI E Voltage Mods

For those who are new to voltage modifying, you may want to read
this guide to get some
basic knowledge of it before proceeding.

The voltage measurement points for VGPU and V Memory are shown below:

vmod2 GeForce 6800 Ultra 512MB PCI E Voltage Mods

To measure, put the red tip of your multi-meter to the point and black tip of
multi-meter to any grounded spot. You will have to measure while the PC is
turned on so be careful not to short out anything.

The default VGPU should read around 1.24v at bootup, while the VMem
should read around 2.07v.

 

vmod1 GeForce 6800 Ultra 512MB PCI E Voltage Mods

For VGPU mod, solder a 100K ohms variable resistor to the point shown
above. The other end of the VR should go to any grounded spot. Set the variable
resistor at maximum resistance of 100K ohms and this will give you a
+0.02v
increase. Tune down the variable resistor slowly to increase voltage.

For VMem mod, solder a 200K ohms variable resistor to the point shown
above. The other end of the VR should go to any grounded spot. Set the variable
resistor at maximum resistance of 200K ohms and this will give you a
+0.01v
increase. Tune down the variable resistor slowly to increase voltage.

Be sure to have good cooling before you attempt these mods as your GPU will
run hotter!

Take note to cool this area well as it will get hot!

vmod4 GeForce 6800 Ultra 512MB PCI E Voltage Mods

 

Good luck on the overclocking!

If you have any questions, drop by our
forums to discuss!