GeForce 9600 GT Voltmods

Introduction

NVIDIA GeForce 9600 GT 512MB is quite an exceptional midrange video card – powered by the freshly-baked G94 GPU core this card offers tremendous value compared not only to earlier generation of similarly priced midrange solutions, but also the more expensive namely more powerful GeForce video cards.
Much like the other members of the NVIDIA G9-family of GPUs, G94 too offers formidable overclocking potential, though, some users may consider the relatively low default operating voltage to hold back the true capabilities of the card.

Grab your soldering iron and let us guide you to extract the last drops of performance out of your NVIDIA 9600 GT - we present you ”GeForce 9600GT Voltmods”.

Disclaimer:
Performing these voltmods will void any and all warranties your video card may have.
You - and only you - are responsible for any damage caused indirectly (or directly) by these modifications.

Overview

Backside view of a GeForce 9600 GT 512MB with NVIDIA reference design circuit board.
Note the chips/areas of interest (red rectangles) and vGPU and vMEM measurement points (blue and yellow rectangles, respectively).

GPU Voltage Mod

vGPU mod for the GeForce 9600GT 512MB involves soldering on several tiny solder pads located near the edge of the circuit board. For the exact location of the solder pads in question refer to the picture in the paragraph: Overview and look for the red rectangle labeled as ”vGPU”. The idea of the modification is to reprogram the vGPU controller chip to aim at a voltage value higher than default. In a sense we're setting a new stock vGPU voltage, as unlike conventional voltage mods, this mod in no way ”deceives” the voltage controller chip. Due to this detail the mod also completely bypasses the extremely aggressive over voltage protection function typical to reference design 9600 GT.


For the record, here is what your unmodded card should look like. The pad-pairs we're going to solder on are labeled here as ”VID2”, ”VID3”, ”VID4” and ”VID5”, each pair of pads is marked with two red dots.
If you're wondering where did VID0, VID1 go – don't bother. This numbering scheme exists only for the convenience of your's truly. :)

• ”open VID” = no connection between the red dots.
• ”bridged VID” = connection between the red dots.
• ”connection” = tiny black surface mount 0Ω resistor. A blob of solder connecting the pair of pads works just as fine.

To achieve 1.15V vGPU voltage one needs to set up the VID pads as instructed above.


Same for procedure for 1.20V.


Here's 1.25V.


And so on. 1.30V.


1.35V.


1.40V.


1.45V.

When powering up the first time after altering the VID remember to check that the actual vGPU voltage is what it was supposed to be.

To measure vGPU take the red probe of your multimeter and touch any of the points marked with dots inside the blue rectangle (see paragraph: Overview), black probe into a ground (Molex connector, eg.). Default vGPU voltage for the GeForce 9600GT is 1.10 V at idle, note that vGPU increases spontaneously by ~0.05 V when entering 3D load. Preliminary reports indicate that vGPU voltages above 1.40 V yield no significant OC headroom.

Caution!
Higher vGPU voltages will cause the heat output and temperature of the GPU chip and the voltage converter circuit to increase dramatically. Make sure you provide adequate cooling on the GPU as well as the whole card when overvolted and overclocked.

Memory Voltage Mod

Locate the chip labeled "51117" on the backside of the card. A 200 kΩ variable resistor is needed for this modification. Solder the variable resistor on the pads pin-pointed in the instructive picture above.

Monitor the resulting vMEM memory voltage with your multimeter: Red probe to the either of the two points marked inside the yellow rectangle (see paragraph: Overview), black probe into a ground. Default vMEM voltage on an NVIDIA GeForce 9600GT is 2.00 V.
2.10 to 2.20 V is usually enough to push the memory frequency as far as it possibly goes.
Your milage may vary.