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*GTX 780Ti Hard Mod For Voltage Control*Special Thanks to@FtW 420For His Help With The Mod and Making This Guide Possible

*DISCLAIMER***THIS GUIDE IS WRITTEN TO USE AT YOUR OWN RISK. DOING THIS MOD WILL VOID YOU WARRANTY AND COULD POSSIBLY DESTOY YOUR CARD. THIS WAS WRITTEN TO THE BEST OF MY KNOWLEDGE AND AS A GUIDE TO ASSIST YOU IN YOUR OWN ADVENTURES INTO UNLOCKING VOLTAGE.**

I did the volt mod on a EVGA GTX 780Ti reference this guide will show you how to test your card for the correct ohm variable resister if you are wanting more voltage then just a regular resister.

There are 2 ways to mod the card first is just a resister with a exact ohm soldered which is one of the easiest to do. The other is a variable resistor which does require more soldering skill and a lot more dangerous as far as destroying the card due to pulling the points directly off the chip.

Voltage Read Point

Below are the points for voltage reading. Since this is hardware modded you will not see the voltage through software such as Precision X or MSI Afterburner. The way to read the voltage will be by using a multi meter to get your readings.

Solid Resistor Mod

There are two points on the back of the card. Shown in the pic below. The points if are right next to the two resistors attached to the board. The later model cards do not have solder already on the points there are a orange looking color and will have to have flux added and some solder put on before you actually start soldering the resistor on. The first batches actually have solder already there so all you need to do is add your flux and go ahead and put your resistor on.

You will solder a resistor between those two points. Different ohms will give different voltages. The voltage it will give can be adjust through Precision X. So 150 ohm in my study gave me 1.268 v reading though a multi meter. So with Precision X volts at 1.21 this is the voltage I get in the image below.

So if I drop the volts down in Precision X to lets say 1.1 v. I would have a reading of 1.158. You take the 1.21 volts in Precision X get your voltage reading with your resistor which in the scenario is 1.268 (VOLTAGE READ OUT ON CARD) - 1.21 (PRECISION X SET VOLTAGE) = 0.058 v difference so you just add that to whatever you set your voltage to in precision x to get a rough idea of the voltage being used. Each resistor offers different voltage increases. Below is a small table of the resistors I used which were available at the

local electronics shop. Feel free to explore more options and let me know the findings and I will add it to the table.

**RESISTOR VOLTAGE**

150 ohm = 1.299 increase of .177 to any voltage set in precision x

220 ohm = 1.254

330 ohm = 1.24

470 ohm = 1.232

As @pharcycle and a few others had pointed out this could also be done using a dipswitch for the mod with this one also so you would have varying ohm resistors at the flip of the switchs.

VARIABLE RESISTOR MODVARIABLE RESISTOR MOD

This mod is a little more dangerous as in the chances of destroying your card greatly increase. You will need a muli meter where you can test the resistance of the point on the card to figure out your correct ohm variable resistor used.

The above picture is for a Titan but the TI is the same except for the ohm resistor used. Test the point on your card to verify that the ohm resistor you use is correct. I test the point with my multi meter on my card and it test at 1002 ohm so you times that by 20 and I come up with a 20K ohm variable resistor needed. This will give you different voltages and allow you to come back to stock settings also.

OHM READING FROM CARD x 20 = VARIABLE OHM RESISTOR NEED

I ordered my variable resistors from Amazon. http://www.amazon.com/gp/product/B008IMQ73Q/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A3UJU66UCNEADW

Now that you got your parts needed its time to do some work. For the VR, pick the middle & one of the 2 outer legs to use & set it to the maximum 20k resistance before soldering it in. I use the outer leg right underneath the screw & cut the other off, that way I always set the VRs to turn the same way to increase/decrease resistance (& voltage) so it doesn't get confusing with multiple modded cards. Were going to use 1 lead & wire going to the mod point beside the ncp4206 controller & the other going to ground (right on the pci-e connector ground pin). The extra leg on the variable resistor you can cut off. Below is a pic of the ground used for the resistor.

I generally use a 2 wire molex type connector & glue that to the back near the VR. With wires coming off the card make sure they are fixed to the card well, they are pretty easy to pull on & don't want to rip the soldered connections. This is key make sure you secure the wires very well to the card as I have destroyed one card by not having it secured and wire got pulled on and ripped the point off the voltage controller and once that happens its pretty much a done deal. Hope you guys enjoy the mods if you have any questions please feel free to ask and I will help and possibly add it to the guide if I have forgotten anything. Will add more pics later once I drain my loop and remove my cards.

Solid Resistor Volt Mod Card running at 1.267 volts

Running the locked 1.21 volts best run