GeForce 9600GT Voltmods

[largon]

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.

[Rhada]

Hi largon!

I tried this voltmod with 1.15v vGPU and set 760 gpu /1900 shaders / 2100 mem and I´m still experiencing black screens. I tried also 750 / 1850 / 2100 and more black screens.
Hmm strange, ´cause it seems to be linked with voltage protection.. How I do to bypass the OVP ?
I´m able to run many games and tests, but some especial games like Colin McRae DiRT and AtiTools freeze my vga after a while (people from other forums have black screens with Counter Strike Source, but I havent the game).

by the way, before the mod, I achieved stable clocks: 740 /1850 /2100 . They are running fine without and with the 1.15v mod.
So, my question is: The vmod is supposed to disable the OVP? If not, how I do to disable it?
Thanks in advance.

[TheGoat Eater]

Largon - could you post a alternative ground spot for the PALIT card that would be on the back of the card and easily soldered?

Thanks to largon I got my PALiT "vanilla" 9600GT to go 845/2112/1000 at 1.3v

[largon]

Rhada,
It's clear that the problem you (and it seems many others) experienced is not due to OVP. OVP (over voltage protection) is triggered when the sensed vGPU exceeds a certain preset multiple of the VID (reference voltage), regardless of GPU load. Also, it's important to notice that OVP is triggered almost immediately, not after a while when the voltage goes above the "forbidden value". What comes to this particular mod and OVP; this mod bypasses OVP because it sets a new VID which directly controls the OVP trigger point. OVP trigger point = VID × value >1.

Most likely the problems are due to OCP (over current protection) which can trigger after a while of 3D load. Unfortunately there's no way to plot a OCP guide atm as the required documents are unavailable.

TheGoat Eater,
Some grounds on the backside (marked with blue dots):

[Rhada]

Originally Posted by largon

Rhada,
It's clear that the problem you (and it seems many others) experienced is not due to OVP. OVP (over voltage protection) is triggered when the sensed vGPU exceeds a certain preset multiple of the VID (reference voltage), regardless of GPU load. Also, it's important to notice that OVP is triggered almost immediately, not after a while when the voltage goes above the "forbidden value". What comes to this particular mod and OVP; this mod bypasses OVP because it sets a new VID which directly controls the OVP trigger point. OVP trigger point = VID × value >1.

Most likely the problems are due to OCP (over current protection) which can trigger after a while of 3D load. Unfortunately there's no way to plot a OCP guide atm as the required documents are unavailable.

Hmmm..I see.. Thanks for the explanation! So, to the OCP the only way is wait for drivers or an bios fix from nVidia. " 9600GT: It's mean to be BSODed "

I was wondering if I need to edit my bios using Nibitor to use as a set with the voltmod, ´cause there is 1.10v to Extra and Voltage 3.. or all bios editing is just a waste of time?
I have another question too
No pencil mod for the memos ? I´m thinking to reach 1100~1200mhz (2200~2400 ddr).. At xtreme systems someone post an pencil mod there. It works? or for the reference card the only way is the variable resistor ?
Thanks dude!

[TheGoat Eater]

thanks a lot

[dadi_oh]

Originally Posted by largon

Rhada,
It's clear that the problem you (and it seems many others) experienced is not due to OVP. OVP (over voltage protection) is triggered when the sensed vGPU exceeds a certain preset multiple of the VID (reference voltage), regardless of GPU load. Also, it's important to notice that OVP is triggered almost immediately, not after a while when the voltage goes above the "forbidden value". What comes to this particular mod and OVP; this mod bypasses OVP because it sets a new VID which directly controls the OVP trigger point. OVP trigger point = VID × value >1.

Most likely the problems are due to OCP (over current protection) which can trigger after a while of 3D load. Unfortunately there's no way to plot a OCP guide atm as the required documents are unavailable.

I agree. I ran some experiments with my card. At higher voltages the card would blackscreen sooner rather than later but even at 1.15V (compared to 1.1V default) I can get black screen at 820MHz core. Also, when it black screens it is not dropping to zero volts. It actually drops to 1.000V exactly so I am guessing that the OCP does not drop V to zero but rather to 1.000V. See my link below. It seems that very shader intensive applications (like firefly forest in 3DMark06) will draw just that little bit extra to cause OCP to kick in. It seems that many of us are riding right on that edge.

http://forums.techpowerup.com/showpo...7&postcount=35

[cbolt67]

Does this work on the 9600GT reference design or something else?

[largon]

It's a reference board-only mod.

[cbolt67]

Thanks for the reply largon. I've seen you on a couple of forums posting on this subject. Thanks for the work you've done on this. You wouldn't happen to know if the MSI N9600GT-T2D512, its the one with the red PCB and fan shroud, is a ref design would you?

[largon]

Based on pics in online reviews (like this) one can see MSI N9600GT-T2D512 is a reference board.

[wolf]

Hey Largon, youve helped me with a Vmod before, so i thought id ask the question...

I have this card : Asus EN9600GT/HTDI/1G



to my knowledge it looks like a non-reference PCB, do you know the vmod points for this PCB? if not and you think you can suss it out, i'd be happy to take some nice pics of the board for you.

Cheeaz in advance,

-Wolf

[largon]

I'd be glad to make you a mod.
=)

And, yep, that's definitely a non-ref board.
I'd guess the mod area is located on the backside of the VRM.

[wolf]

Cheers dude, your an absolute legend.

Ill take some nice pics of the card asap and upload them here for you.

i was scowering the net for a guide, then i remembered, you da man.

ive gotten the core on this baby to about 22 degrees C under full load with some creative cooling, so i know shes not temp limited with my max clocks of 800/2000 on the core.

[RadeonX2]

ei guys any1 know how to disable OVP?

I have tried 1.25 & 1.2 vcore but OVP kicks in @ 1.15 OVP was gone but limited my OC to 735MHz on core @ stock vcore only 720MHz pls help

[largon]

RadeonX2,
What are your symptoms?
When and what happens when "OVP kicks in"?

[RadeonX2]

Originally Posted by largon

RadeonX2,
What are your symptoms?
When and what happens when "OVP kicks in"?

running 3Dmark06 return to proxycon was fine until I get to firefly forest immediate blackscreen fan ramping to 100% w/ 1.25 & 1.2 vcore...

I have a reference design Inno3D 9600GT oc 512mb 256bit

[largon]

RadeonX2,
The thing is, the "VID mod" described in this article bypasses OVP as it sets a new VID which also controls the OVP setpoint.
This black screen issue would seem to be related to OCP (overcurrent protection). But, it appears it is not that simple. People have reported that bumping the OCP setpoint (increasing resistance between GND and pin#15) does not prevent the black screens, either.



Reference 9600GT is a reeeeally weird card. Some people have huge black screening problems and some don't have any issues. One guy I know has two identical cards of which one works fine, while the other black screens like crazy, at a given voltage...

[RadeonX2]

Originally Posted by largon

RadeonX2,
The thing is, the "VID mod" described in this article bypasses OVP as it sets a new VID which also controls the OVP setpoint.
This black screen issue would seem to be related to OCP (overcurrent protection). But, it appears it is not that simple. People have reported that bumping the OCP setpoint (increasing resistance between GND and pin#15) does not prevent the black screens, either.



Reference 9600GT is a reeeeally weird card. Some people have huge black screening problems and some don't have any issues. One guy I know has two identical cards of which one works fine, while the other black screens like crazy, at a given voltage...

thanks for d heads up... I might live this black screen problem till I get a new card underclocking was one of my options that work but only games like F.E.A.R and CS:S that I have mostly blackscreen... so it was OCP not OVP