# GeForce 9600GT Voltmods



## largon (Apr 18, 2008)

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## Rhada (Apr 22, 2008)

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.


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## TheGoat Eater (Apr 22, 2008)

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


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## largon (Apr 22, 2008)

*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):


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## Rhada (Apr 22, 2008)

largon said:


> *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!


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## TheGoat Eater (Apr 23, 2008)

thanks a lot


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## dadi_oh (May 1, 2008)

largon said:


> *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/showpost.php?p=770507&postcount=35


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## cbolt67 (May 10, 2008)

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


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## largon (May 10, 2008)

It's a reference board-only mod.


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## cbolt67 (May 10, 2008)

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?


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## largon (May 10, 2008)

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


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## wolf (Oct 12, 2008)

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


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## largon (Oct 12, 2008)

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.


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## wolf (Oct 12, 2008)

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.


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## RadeonX2 (Oct 12, 2008)

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


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## largon (Oct 13, 2008)

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


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## RadeonX2 (Oct 13, 2008)

largon said:


> *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


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## largon (Oct 13, 2008)

*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...


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## RadeonX2 (Oct 13, 2008)

largon said:


> *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.
> 
> ...



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


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