8800s OVP Mod ......

[hipro5]

Did you expected it?.......Get it......THAT simple and as promised......:D

This picture includes the VGPU and the OVP of the 8800GTX and 8800 Ultra VGAs......8800GTS is SIMILAR but in anoter position of the PCB......;)

CREDITS for the VGPU Mod goes to Shamino and vr-zone.....;)

http://www.hipro-tech.com/images/hipro5/NVIDIA_8800_Mods/8800_VGPU_OVP_Mods.jpg


Here is the OVP Mod in a closer look.....:)


http://www.hipro-tech.com/images/hipro5/NVIDIA_8800_Mods/8800_OVP_Mod_1.jpg


......and here's an alternative method for more "hardcore" people.....:D :p:


http://www.hipro-tech.com/images/hipro5/NVIDIA_8800_Mods/8800_OVP_Mod_2a.jpg

http://www.hipro-tech.com/images/hipro5/NVIDIA_8800_Mods/8800_OVP_Mod_2b.jpg


By doing so, you will NOT ENCODE this f(l)uken VGA's shut down and core powering down problem any more..... ;)
You'll ONLY have to deal of how much VGPU you will feed it until it produses Core artifacts during a bench....
IF you get a "freezing" during a bench, then your VGA's core CAN'T go higher than that...... :D :p:

Happy NVIDIA VGA Overclocking and DON'T pass my scores..... :D :p:


.

[eva2000]

Sweet. i know a few Aussies who have been waiting for this :)

[DMH]

Veryy good,you don't know the exact position for the GTS???:D

[harleybro]

Thank you Hipro!!!!!!!!!!! Is it possible to use a 50Kohm trimmer. I take it the resistance you measure is across the resistor with the trimmer soldered in place?

[hipro5]

Veryy good,you don't know the exact position for the GTS???:D

Yes I know it but I have to picture it first....... :D
I'll do it tomorrow..... ;)


Thank you Hipro!!!!!!!!!!! Is it possible to use a 50Kohm trimmer. I take it the resistance you measure is across the resistor with the trimmer soldered in place?

Yes you can.....This will give you about 5.03 measuring RED POINT to ground when the trimmer is FULLY "opened" (at 50KOhms).... ;)


Sweet. i know a few Aussies who have been waiting for this :)

I know at LEAST ONE.....dinos.....:D

[dinos22]

:up:

[largon]

Corresponding resistor on 8800GTS:
http://img229.imageshack.us/img229/8062/g80gtsovpfv3.jpg

[T_M]

Hipro5, thank you master :)
Will test it today

[Oliver]

You are doing it again.

Good work.

Keep pushing it.

[hipro5]

Thanks guys.....:)

For the 8800GTS is the resistor which largon pointed out..... ;)

You can trimm the resistor to show you down to 4.7 - 4.8KOhms....:)

[massman]

Thank you for sharing, Hipro ;) :D

[SF3D]

Thanks Hipro! Good attitude like always :up:

Have to do these as soon as possible...

[K404]

Im expecting more ORB abuse soon :D

Everyone needs to go back and bench again :D:D

[dinos22]

Thank you for sharing, Hipro ;) :D

this is a pretty big deal isn't it ;) and he delivered

[Harshal]

Thanks Hipro!! This is for others as I am not in VMODs yet!!
Yeah.. I reallly need to get into this game of soldering first & then to modding without killing stuff. :)

[largon]

Just did the mod "hardcore" style:
http://img98.imageshack.us/img98/8500/img4089rtn6.th.jpg (http://img98.imageshack.us/img98/8500/img4089rtn6.jpg)
Desoldered the 5.2KOhmer then replaced with a 4.7KOhmer...
It seems vGPU dropped by ~0.1v consequently - but nothing a little poking of the vGPU mod will not fix though.
Will report if it helps OC'wise. :p:

[NightRaven]

wow this is big news! didnt know of it till the Aussie/s told me about it then i headed this way to find some hipro5 action! and i found it! coolness! will be doing this for my ultra when it comes back from RMA AFTER THREE.. yes 3... yes THREE months of waiting.

thanks hipro5!

[T_M]

Hipro, can you please share the theory behind this mod? What is the resistor connected to etc?

[massman]

this is a pretty big deal isn't it ;) and he delivered

Yeap, I don't own any 8800-series card, though I'm pleased he shared the mod. :yepp:

[giorgioprimo]

Thanks George :)

[largon]

Well this is odd.
Tested voltage stability with 3DMark06 on gaming stable freqs of 729/1890/2160:
1.36v (1.33v after droop): OK
1.54v (1.51v after droop): instant GPU powerdown

[wittekakker]

Seems to be working great here, just ran 1.6V 3D, that is 1.7V 2D with my 8800GTS :)

Thx for sharing Shamino!

EDIT: hmm, still can't beat 720/1600/1040, protection kicks in at higher clocks :/

[T_M]

George, I have soldered a 100k on my 8800 Ultra.
As i trim, it starts from high resistance and goes down.
Once i reach ~7.57k it suddenly jumps down to ~3.362k.

Is the objective to raise the resistance across that resistor? If so, is 7.6k to ground OK?

[largon]

Thx for sharing Shamino!:stick:
Only the vGPU mod (which has been around for ages already) is from Shamino, OVP is all Hipro's handwriting.

Too bad my card has not gained from either mod, the vGPU nor the OVP.
Stuck at 729MHz no matter the voltage. :(

[hipro5]

Well this is odd.
Tested voltage stability with 3DMark06 on gaming stable freqs of 729/1890/2160:
1.36v (1.33v after droop): OK
1.54v (1.51v after droop): instant GPU powerdown

Maybe it's shuts down from over temperature protection or something....;)


George, I have soldered a 100k on my 8800 Ultra.
As i trim, it starts from high resistance and goes down.
Once i reach ~7.57k it suddenly jumps down to ~3.362k.

Is the objective to raise the resistance across that resistor? If so, is 7.6k to ground OK?

Are you sure you have soldered to the same resistor?......If you have soldered an 100K trimmer, even fully opened, it shouldn't show you more than 5.12K.....:)


Seems to be working great here, just ran 1.6V 3D, that is 1.7V 2D with my 8800GTS :)

Thx for sharing Shamino!

EDIT: hmm, still can't beat 720/1600/1040, protection kicks in at higher clocks :/

Same here too - Maybe it's shuts down from over temperature protection or something....

[largon]

hipro5,
The GPU is watercooled and peaking @ 46ºC. Can't be the temps.
And it trips literally instantly when 3D is started, no time for temps to go overboard.
Dunno what's going on with card... :confused:
I guess the next step is to rebuild the vGPU circuitry... Got the chokes and caps ready...

[wittekakker]

George, I have soldered a 100k on my 8800 Ultra.
As i trim, it starts from high resistance and goes down.
Once i reach ~7.57k it suddenly jumps down to ~3.362k.

Is the objective to raise the resistance across that resistor? If so, is 7.6k to ground OK?

The mod explains to start at 100k, lowering resistance would do the trick I guess.


:stick:
Only the vGPU mod (which has been around for ages already) is from Shamino, OVP is all Hipro's handwriting.

I'm sorry, let's say they both rock, I appriciate what they have done for this community :)


Maybe it's shuts down from over temperature protection or something....;)

Small 3D Mark 2001 runs, temps under 70°C, nat that bad considering it is aircooled and has 1,6V on it's head :)


Are you sure you have soldered to the same resistor?......If you have soldered an 100K trimmer, even fully opened, it shouldn't show you more than 5.12K.....:)

I got around 4,8k after taking 50k or 100k VR to ground, I've even lowered it to 4,2k but no better results. What I did notice that, once I changed from 4,8k to 4,2k, sudenly the output voltage dropped with 0,1Volts, even more. Not that bad, just a bit weird so tee such things happening :)


hipro5,
The GPU is watercooled and peaking @ 46ºC. Can't be the temps.
And it trips literally instantly when 3D is started, no time for temps to go overboard.
Dunno what's going on with card... :confused:
I guess the next step is to rebuild the vGPU circuitry... Got the chokes and caps ready...

Well, I haven't spend much time testing this new mod, only 30min, though I was working on a way to change the over current protection trip point, maybe that helps us too. Most of my free time is not spend on overclocking though, I don't know when I ever get my results online, I have to do a lot of research since I'm not an engineer in electronics :)

Hipro, can you please explain me/us how you got this mod working? The datasheet learns us totally nothing. It's not like a feedback loop it seems, no resistor devider, or maybe the second component is located somewhere on the other side of the board? Anyway, the resistor is connected to ground and to the PWM controller, that's all I can say for now. Hipro, would you be so kind to explain us how you got this working, I'm very interested in this stuff, I would possible learn a lot from this :)

[T_M]

Are you sure you have soldered to the same resistor?......If you have soldered an 100K trimmer, even fully opened, it shouldn't show you more than 5.12K.....:)

Measuring the resistance across the resistor prior to the mod (or to ground) i get 3.xxk ohms. Adding the 100K with it at max resistance i get 9x.xxk Ohms. Then by reducing the VR it drops down, until i hit 7.xxk then it suddenly trips over to 3.xxk.

[dinos22]

temp protection should kick in around 120C

but try lowering your GFX card clocks and bumping voltage gratually largon to see where the limits are

[hipro5]

Measuring the resistance across the resistor prior to the mod (or to ground) i get 3.xxk ohms. Adding the 100K with it at max resistance i get 9x.xxk Ohms. Then by reducing the VR it drops down, until i hit 7.xxk then it suddenly trips over to 3.xxk.

:confused:

by default - as the VGA is - it's resistor IS 5.2K.....How do you measure by default 3.xxK.......?.....:confused:


Some updates:

A friend of mine did the OVP Mod on his 8800GTX VGA....Though he got a bit more overclockability out of it (he gained some more MHz out of the Core), the "powering down" still exists.....
I asked him to measure the Vdroop of it......From 1.61V it went down to 1.54V during bench....
SO I think that this is the cause to work properly the OVP Mod.....One resistor is the "start up" voltage and the other resistors "tracks" the "spikes" during runing.....So if a "spike" of Core Voltage is high, the VGA powers down.....
During Vdroop (running a 3D), the VGPU NOT only goes down BUT produces HIGH "spikes" as well during a "relaxed scene" of the 3D.....
That's the reason that it worked perfect for me......
I only have "freezings" when my VGA can't go higher.......NO power down.....During a freezing at 1.75V (idle), I STILL measure 1.72V (load).....NO power down......Maybe coz of the "extra" components I have added on it for less Vdroop....
I'll check it out.....

http://www.hipro-tech.com/images/hipro5/ASUS_Striker/8800Ultra_moded.jpg

[T_M]

In a few hours time ill post up pics of the mod i performed on my 8800 Ultra, along with pics of measuring the resistance both with and without the mod.
Any requests?

[giorgioprimo]

I only have "freezings" when my VGA can't go higher.......NO power down.....During a freezing at 1.75V (idle), I STILL measure 1.72V (load).....NO power down......Maybe coz of the "extra" components I have added on it for less Vdroop....
I'll check it out.....[/B]



did you add some capcitors as you usaully do ?

come on ! let we know your secrets :up:

[hipro5]

did you add some capcitors as you usaully do ?

come on ! let we know your secrets :up:


Photo is above...... ^

[T_M]

Hipro, could it possibly be the fact that im performing the mod after the vcore mod is done? Is there any interaction?
Anyway, about to head home and will have pics up in a few hours.

[TiN_]

T_M

you can do ovp mod anytime, It will noT interact in bad way ;) Just will give you more room for raising vcore, if you had issues with card powerdown NOT due temperatures..

[T_M]

Thanks TiN but i kinda knew that.
WHat i didnt know was why my card was behaving totally differently just on the resistances than what Hipro suggests.

Measure my card again, this time with mod removed and every single time i measure it i get a different reading. Tried cleaning the resistor up and still the same. Either 2.1M, 3.2K, and sometime flashes of 5.3K.
Have removed the mod for now, let some more guinee pigs confirm it on an Ultra. Mine's XFX btw.

http://img.photobucket.com/albums/v310/T_M/Picture001.jpg

[hipro5]

Thanks TiN but i kinda knew that.
WHat i didnt know was why my card was behaving totally differently just on the resistances than what Hipro suggests.

Measure my card again, this time with mod removed and every single time i measure it i get a different reading. Tried cleaning the resistor up and still the same. Either 2.1M, 3.2K, and sometime flashes of 5.3K.
Have removed the mod for now, let some more guinee pigs confirm it on an Ultra. Mine's XFX btw.

Mine's ALSO XFX......Brand doesn't make ANY difference.....You buy only .....brand and the exact same product....;)

Please check you battery in your multimeter.....;)

[TiN_]

T_M

All 8800 cards are made on two plants, and retailers like ASUS,XFX etc just put their lable\cooling on already manufactured cards.

Agree with hipro5, try to change your multimeter bat or try another multimeter.

[T_M]

I had expected those responses and probably should have told you guys already.
Im using a Fluke 114 and the battery is only a couple months old.
The probes have been cleaned with isopropyl alcohol as has the resistor.
It reads totally reliably on other resistors (e.g. the one right next to the OVP one)

Please can someone else read their resistance

[TiN_]

T_M

couple of months is pretty much time

There is no miracle, and resistance cannot jump in such big difference on it's own. Maybe you have bad cable connection between DMM and probes, check everything. Try to reverse probes, maybe your multimeter charges some capacitor on curcuitry (in measuring resistance mode DMM puts some voltage (1-2V usually) to probes, and reads difference).

[chispy]

Thanks Hipro and Shamino, I was waiting for this Mod for a long time , thank you alot for sharing your knowledge with the community.

chispy.

[largon]

hipro5,
What are the specs of those electrolyte caps you used to beef-up the vGPU filters?
Wouldn't ceramic caps have been better?

And did you remove the original vGPU inductors or are the coils "piggy-backed"?

[hipro5]

@ chispy: you're welcome...:)


hipro5,
What are the specs of those electrolyte caps you used to beef-up the vGPU filters?
Wouldn't ceramic caps have been better?

And did you remove the original vGPU inductors or are the coils "piggy-backed"?

According to THIS post of mine (http://www.xtremesystems.org/forums/showpost.php?p=2486756&postcount=37) Digital VRM NEEDS electrolytic caps as well.... ;)
I have added some 2200uF/6.3V plus some chokes in PARRALEL with the existing ones so to:
a. avoid the big Vroop
b. Lower the resistance of each coil
c. filter better the output VGPU

Ceramic caps will do bullsh.. as for the "spikes" of the VGPU and filtering during load/semi-load/idle....;)

[T_M]

So, has anyone else tried it yet?

[7499richard]

i would try it...but it doesnt make much sense to me....and it seems as though the only one with success is OP.

I think the OVP on this card is high...because I have set mine to about 1.75V and run half way through 3dm06 and then it shuts down. The card never brok 48degrees C so it was notheat related. I think it must have been a large voltage spike or something that set it off..

Personally I think clean DC voltage is far more important for the gpu if you want stability. So beefing up the supply is important to me. That is what I want to do...so if the OP...or anybody else for that matter, has any guides or pics of how to do this pls post with part numbers or values for the upgraded components.

[cowie]

thanks *(again) for mod
will try gts mod with pencil tonight,i should easy get that res. down with pencil.
plus i need some ice cus this is no mod for air.

[cowie]

i penciled down from 5,22 to 4,88.on a a3 gts.
it lowered my core volts to 1.16 1.14 load?so i cleaned it off and restarted back to 1.51 1.48 load.
did not try to bring up volts, is this what needs to be done cus that would "bottom" out my vr no?
i will try for more findings asap

[giorgioprimo]

wich value for the chokes ? (http://www.rs-components.it/cgi-bin/bv/rswww/searchBrowseAction.do?D=induttanza%20toroidale&Nr=AND%28avl%3ait%2csearchDiscon_it%3aN%29&Ntk=I18NAll&Nty=1&Ntt=induttanza%20toroidale&Dx=mode%20matchpartial&Ntx=mode%20matchpartial&N=0&name=SiteStandard&forwardingPage=line&R=2508973675&callingPage=/jsp/search/search.jsp&BV_SessionID=@@@@1945811026.1192747328@@@@&BV_EngineID=ccciaddmffjmfgjcefeceeldgkidhgh.0&cacheID=itnetscape)
http://docs-alliedelec.electrocomponents.com/Images/Products/Small/967-8766.jpg


Photo is above...... ^

[hipro5]

wich value for the chokes ? (http://www.rs-components.it/cgi-bin/bv/rswww/searchBrowseAction.do?D=induttanza%20toroidale&Nr=AND%28avl%3ait%2csearchDiscon_it%3aN%29&Ntk=I18NAll&Nty=1&Ntt=induttanza%20toroidale&Dx=mode%20matchpartial&Ntx=mode%20matchpartial&N=0&name=SiteStandard&forwardingPage=line&R=2508973675&callingPage=/jsp/search/search.jsp&BV_SessionID=@@@@1945811026.1192747328@@@@&BV_EngineID=ccciaddmffjmfgjcefeceeldgkidhgh.0&cacheID=itnetscape)
http://docs-alliedelec.electrocomponents.com/Images/Products/Small/967-8766.jpg

Link doesn't work....Get some .68uH at 25A+ each (at 25*C).....:)

[giorgioprimo]

Thanks :)



Link doesn't work....Get some .68uH at 25A+ each (at 25*C).....:)

[giorgioprimo]

George, i looked all around the web but for me is difficoult to find the value you raccomanded,

may you please indicate the right component ( or something similar ) here (http://www.distrelec.com/ishopWebFront/search/luceneSearch.do?filterCategory=&showImage=true&dispatch=goTo&filterPhrase=&pageSize=25&filterVendor=&pageNum=1)
or here (http://www.distrelec.com/ishopWebFront/search/luceneSearch.do?dispatch=find&showImage=on&artnrPhrase=&typePhrase=&keywordPhrase=toroidale&vendorPhrase=) ?

Thanks

Link doesn't work....Get some .68uH at 25A+ each (at 25*C).....:)

[hipro5]

George, i looked all around the web but for me is difficoult to find the value you raccomanded,

may you please indicate the right component ( or something similar ) here (http://www.distrelec.com/ishopWebFront/search/luceneSearch.do?filterCategory=&showImage=true&dispatch=goTo&filterPhrase=&pageSize=25&filterVendor=&pageNum=1)
or here (http://www.distrelec.com/ishopWebFront/search/luceneSearch.do?dispatch=find&showImage=on&artnrPhrase=&typePhrase=&keywordPhrase=toroidale&vendorPhrase=) ?

Thanks

Hmmm......They don't have some with so high current..... :(
Tell you what.....Find a burned ABIT IC7 mobo and unsolder it's VCore chokes.... ;)

[giorgioprimo]

have found some 50uH or 19uH 25A, is ok or i need abosolutly .68uH ? ( sorry but I don't understand wat uH value, means )

[hipro5]

have found some 50uH or 19uH 25A, is ok or i need abosolutly .68uH ? ( sorry but I don't understand wat uH value, means )

NO - NO - NO ...... NOT xxuH......You NEED 0.68uH - NOT EVEN 1.0uH

[Johnny Bravo]

George this mod based on the vmax terminal?

http://www.primarion.com/PrimarionMain/Documents/PDB-3540.pdf

[TiN_]

I'm not George, but yes, think so. :)


George this mod based on the vmax terminal?

http://www.primarion.com/PrimarionMain/Documents/PDB-3540.pdf

[Xtasy]

hey i have a small problem, well i did the your mods to some 8800 GTX and the smd for vgpu fell off. there aren't solderpoints anymore so i cant solder the smd back on board. how do i manage to bridge that :banana::banana::banana::banana:ing smd :/

[hipro5]

George this mod based on the vmax terminal?

http://www.primarion.com/PrimarionMain/Documents/PDB-3540.pdf

Yes Johnny.....BUT there MUST be a little Vdroop on the VGPU so NOT to produse to high VSpikes so to work properly....:)



hey i have a small problem, well i did the your mods to some 8800 GTX and the smd for vgpu fell off. there aren't solderpoints anymore so i cant solder the smd back on board. how do i manage to bridge that :banana::banana::banana::banana:ing smd :/

Hmmm.......Now you're screwed.... :D
....now you HAVE to find the "line" that goes onto the VCore leg of the chip and solder on it - NOT YOU, ask for someone else to do this for you :D j/k - ......

[wittekakker]

NO - NO - NO ...... NOT xxuH......You NEED 0.68uH - NOT EVEN 1.0uH

Why not? Frequency related?

[Johnny Bravo]

Yes Johnny.....BUT there MUST be a little Vdroop on the VGPU so NOT to produse to high VSpikes so to work properly....:)


Very true ;) Did you have any luck getting the full datasheet?

[hipro5]

Very true ;) Did you have any luck getting the full datasheet?

Unfortunately no.... or else I could see if I could sovle the "VDroop problem"..... :(

[dinos22]

Very true ;) Did you have any luck getting the full datasheet?

it's under NDA and they won't release the data
i tried a few months ago

[Johnny Bravo]

gutting wondered if we were all in the same boat :(

[T_M]

Well it seems i have nothing better to go on (no other people trying it) so ill just have to try my luck and redo the mod, but without being able to measure the resistance.

Hipro, approximately how many turns down in resistance on your 25 turner did you have to make to get the ~5.1K reading?

[oohms]

Found the resistor for the 8800GT:

http://i30.photobucket.com/albums/c306/oohms/misc%20oc/img0818bbvp3mod.jpg

[7499richard]

So does this mod help anybody?

Reading the posts it does not really seem so...

Is there anyway to get a linear supply at say 1.6//1.7//1.8 volts and power the core with that? That is really what is needed to get nice clean dc to the core and then I am sure the MHz would sore, and so would the stability....

[wittekakker]

So does this mod help anybody?

Reading the posts it does not really seem so...

Is there anyway to get a linear supply at say 1.6//1.7//1.8 volts and power the core with that? That is really what is needed to get nice clean dc to the core and then I am sure the MHz would sore, and so would the stability....

X38 mainboard PWM should work out very well :)

[7499richard]

well I don't no too much about completing the mod, but I am an electrical technologist and we use linear power supplies...such as a techtrol, to supply analog equipment to ensure accurate reference voltages. The voltage does not fluctuate under load and it stays very "clean". With a scope meter the wavforms will stay nice and flat with varying loads. And that is exactly what is needed for the gpu to operate consistently and stable.

And looking at a video card the circuitry is not capable of providing what is needed.

Any thoughts from anybody?

[wittekakker]

1,6V 100A, think you're left behind building one yourself.

[7499richard]

I dont follow what your post meant. 1.6v, 100A, is that supposed to be the ratings of such a power supply?

Where does 100A come from, I must totally misunderstand what your post mean because if 100A went through any part of the card it would break?

Anyway even if you found say a 3V supply, or a 5V supply you could set yourself up a series circuit with some big resistors to drop the voltage down. Use a big heatsink and a couple fans to deal with the heat.

Is this a legitimate solution? What kind of current would an 8800GTX's core draw at say about 1.7V and 760...800MHz core speed?

[wittekakker]

I dont follow what your post meant. 1.6v, 100A, is that supposed to be the ratings of such a power supply?

Where does 100A come from, I must totally misunderstand what your post mean because if 100A went through any part of the card it would break?

Anyway even if you found say a 3V supply, or a 5V supply you could set yourself up a series circuit with some big resistors to drop the voltage down. Use a big heatsink and a couple fans to deal with the heat.

Is this a legitimate solution? What kind of current would an 8800GTX's core draw at say about 1.7V and 760...800MHz core speed?

The standard Primarion PX3540 is made to handle up to 200A, looking at the other main components, I'd say +100 Ampére is a possibility when pushing the GPU to the maximum.

[7499richard]

ok i totally disagree with you and you need to give more of an explanation as to where you come up with these current figures.

Have you ever seen a cable that is designed to carry 100A? Its not a tiny little kiddie cable, like the components on a video card, there is no way a video card has that kind of current travelling through it. Do you realize how hot it would get?

Maybe I am totally wrong but everything I have seen out in industry tells me that there is no way there is anywhere near 100A going through a video card.

[hipro5]

The standard Primarion PX3540 is made to handle up to 200A, looking at the other main components, I'd say +100 Ampére is a possibility when pushing the GPU to the maximum.

OVER 140A at 1.65Volts and 1GHz Core... ;)

[7499richard]

i dont understand this at all

can someone convince me, there is nothing on the card that can carry 100A, so this makes no sense to me. The core is drawing that current from somewhere on the card so the current is traveling through the card to get there

[wittekakker]

ok i totally disagree with you and you need to give more of an explanation as to where you come up with these current figures.

Have you ever seen a cable that is designed to carry 100A? Its not a tiny little kiddie cable, like the components on a video card, there is no way a video card has that kind of current travelling through it. Do you realize how hot it would get?

Maybe I am totally wrong but everything I have seen out in industry tells me that there is no way there is anywhere near 100A going through a video card.

At 220V, yes, things would be different, but we are talking about only 1 and a half Volts here. Ever woundered why so much people use water to cool their processors instead of air, because the things produce over 100 Watt overclocked, devided by the that 1,5V.....

[7499richard]

ok yes that makes sense now, thanks for clearing it up.

so is there any way to beef up the supply or anything to correct these horrible voltage spikes that are shutting down our cards, I really want to be able to oc my card more, as I am going to keep it for awhile longer now that it doesnt look like there will be another high end card from nvidia for a little while.

Is that X38 PWM a viable option?

[wittekakker]

ok yes that makes sense now, thanks for clearing it up.

so is there any way to beef up the supply or anything to correct these horrible voltage spikes that are shutting down our cards, I really want to be able to oc my card more, as I am going to keep it for awhile longer now that it doesnt look like there will be another high end card from nvidia for a little while.

Is that X38 PWM a viable option?

Not really, mainboard PWM is not easy to reconstruct, not like lineair controllers. You could use a high-end mainboard because of its better PWM design, but I don't really see anyboddy doing it, costs to much :)

[7499richard]

well have you added capacitors or anything else to your card to increase stability?

If so what did you use and where did you get it?

Also were there any real improvements in overclockability after the mod was done?

[wittekakker]

well have you added capacitors or anything else to your card to increase stability?

If so what did you use and where did you get it?

Also were there any real improvements in overclockability after the mod was done?

Look at Hipro's post, he has done cap modifications. I'm planning on doing some too, can't find the right coils, but I do have some 6,3V 1800uF caps from a dead MSI-6758 P4 mainboard.

[G H Z]

Unfortunately no.... or else I could see if I could sovle the "VDroop problem"..... :(

hipro I think the 8800 GPU mod was located using the PX3535 datasheet, I had this saved on an old drive so maybe this will help for droop :up:

http://img.photobucket.com/albums/v31/canny/px3535_pinout.jpg

OVP mod is connected to pin5 upper bank (from right), Fault2 - based on largon's GTS pic on page #1

[G H Z]

I have another question, can someone tell me what pin the vcore mod traces to (based on the datasheet)? It's not OUT4 (pin 6) as I had previously read somewhere.

[hipro5]

I have another question, can someone tell me what pin the vcore mod traces to (based on the datasheet)? It's not OUT4 (pin 6) as I had previously read somewhere.

Resistor's inner is connected with OUT4.... :)

[G H Z]

Hmm, then why isn't there apparently any connection to it? :)

http://img.photobucket.com/albums/v31/canny/out4_null.jpg

[hipro5]

Propably coz they don't use the schematic above.... ;)

Problem is that I cannot understand it.....Why we use an output to Vmod the VGPU of the VGA?.... :confused:
Maybe they have connected OUT4 with Vsence directly and that is a fine explanation of the HUGE Vdroop this VGA has.......I'll investigate it more.....;)

Can someone measure the Vdroop at the DEFAULT Volts of the VGA?....Is it big or not?....

[wittekakker]

PX3535 is different from PX3540, just look at the amount of VID pins this chip has. Another example, the ISEN pins are different located, I've posted this somewhere on this forum. I don't think we can use the PX3535 datasheet as example to modify the PX3540.

[Oc-Ghost]

Why look at a different chip? google is your friend ;)
PX3540 (http://208.109.51.75/PrimarionMain/Documents/PDB-3540.pdf)

[wittekakker]

Why look at a different chip? google is your friend ;)
PX3540 (http://208.109.51.75/PrimarionMain/Documents/PDB-3540.pdf)

:welcome: in the 8800 modding game.

We are way past that one, the problem is that the product sheet is not a full datasheet with pinouts etc.

[T_M]

The other day i went in blindly (since my resistance measurements are all over the place still for that resistor) and soldered on the 100k again, with the ground line on an aligator clip. Got the system running without the mod engaged and then clipped on the ground. Nothing burned up and the system ran 3DMark fine.

That was right before i killed the mobo of course so didnt get to test whether the OVP was actually adjusted heheh.

[Alexxx650]

Hi everyone. I need your help. There is card 8800 runaways before frequencies 729 on water with vGPU of the chip 1.490 card can work at 756 but more 1.510 put (deliver) can not since card does not work. The Question: why OVP modes do not work at 8800Ultra? Water running +8 degrees. The Card in simple 28 idle in load 33.

My system:C2D Conroe SL9S7 E6700@3900 487.5x8 1.4875 Swiftech Apogee™ GT
ASUSTeK Striker Extreme; nForce680i SLI; vDroop mod, NB/SB - Swiftech MCW30
Crucial Ballistix 2 x 1024 / Micron D9GMH 533@975 4-4-4-4-T1-16-20-6-7-3 2.3250v Dominator AirFlow
Видеокарта: PCI-E 768МБ Leadtek WinFast PX8800 Ultra 783(1998)/1260 OVP Mod, vGpu 1.489, Vmem 2.24, EK, PCI-E 100@125
320 Гб 3200YSx2 (RAID edition) NVIDIA STRIPE 596.18G
Thermaltake Toughpower 650W V2.2 (20/24+4+6+8pin, d140мм)
DVD RAM Plextor PX-760A
Logitech G15
Razer Copperhead
Razer Mantiz Speed
Technics RP-DJ1210
Microphone: SM58 Vocal
Microsoft Windows XP Professional x64 Edition

[hipro5]

It's simple......Think about "CPU".....When you feed your VCore with more Voltage, it stops "handling" it when you go too high....IF you put it under DI or LN2 for example, it can handle this high VCore and it handles even more than that......This way is how GPU handles the VGPU.....It's the same thing...:)

[T_M]

At only 1.51V you are not going to have to worry about OVP.
OVP generally kicks in around 1.65V+.

On my card my current max is 1.662/2.25V when running 938/1188MHz before i hit OVP and the system reboots then registeres only 0.100V vGPU. Thats when i know i failed due to OVP.

George, not sure if you missed my question earlier in this thread:
About how many turns of the 100K VR are required to get the desired 5.1K OVP resistance?
Because i cant measure resistance properly (as discussed before) im just running it blindly.

[Alexxx650]

Thank for answers. It turns out to me it is necessary to make better cooling, instead of OVP?

[T_M]

Yes, better cooling means you can put more volts thru.
Once you are using Dry Ice or better, then you should worry about OVP :)

[oohms]

hipro5 what about putting a resistor in series with VSENP and/or VSENN?

http://208.109.51.75/PrimarionMain/Documents/PDB-3540.pdf

[hipro5]

hipro5 what about putting a resistor in series with VSENP and/or VSENN?

http://208.109.51.75/PrimarionMain/Documents/PDB-3540.pdf

I think that we already have a BIG Vdoop on this design.....IF we put a resistor as you say, it'll make things even worse as for Vdroop.....
We HAVE to find out hte full datasheet of the IC so to search the design and eliminate the Vdroop of it if possible....:(

At least in my way of doing it, I have NEVER encoded shut down problems due to OVP.....I have frezzings if the core goes too high and that's it....I meassure the VGPU and it's there..... :)

[wittekakker]

I've added 3x 1800uF caps to my GT, and changed from Thermalright HR-03 to chilled water, no way my card would go any higher then before, removed all my mods now because there is no way I can get this card clocking any further. Do the inductors really boost the Vdroop that much?

[hvtecgr]

Hi hipro!!!my dfi p965 has the primarion 3539!!!I've searched a little and found another datasheet from other company which makes the excact same chip and i have the full datasheet from that!3539 has a pin named vr_ready and i came in conclusion that this must controll the vdroop!!But i'm not sure how it changes from 0 to 1!!!I don't know if that helps cause i don't see any pin named vr_ready in px3535!!!

[T_M]

Interestingly, my friend pro has measured his OVP resistor to find an inconsistent value too, so its not just me.

[T_M]

Yesterday i ran into trouble with my Ultra.
My vGPU mod was going weird, so i removed it to reapply the connection to resistor.
Unfortunately it appeared that the resistor was damaged (or at least the pad).
After much messing around and variouys attempts to solder it, i finally got what i thought would work.

Then i took the opportunity to check my OVP mod again, and while i was still getting different readings, occasionally i would get ballpark correct ones, which allowed me to adjust the VR to give me the required 5.1k.

Plugged the card back in to check my repair work, and holy :banana::banana::banana::banana: 2.52V!
Looks like the OVP mod works :D
Pity about my vGPU mod.... so i swapped the 500 Ohm for a 10K, reran and the card is back working again, presumably with no OVP :)

[dinos22]

2.52 :D :eek: :shocked: :D

we need the ovp for 8800GT

people are reporting OVP kicking in at 1.3v which is only good for 1GHz on core with dice (lol ONLY haha) :eek: :D

[Mysterfix]

2.52 :D :eek: :shocked: :D

we need the ovp for 8800GT

people are reporting OVP kicking in at 1.3v which is only good for 1GHz on core with dice (lol ONLY haha) :eek: :D

Yeah, i'd like to at least go 1.35v for some 900mhz action on water.:up:

[T_M]

Yeah lol, i turned off pretty quick ;)

In addition to that, I almost burnt the card last night, straight after writing a drunken post on i4 i started playing with the volts, not realising my probe was in the vCore (CPU) read not vGPU. Kept turning and wondering why my volts werent budging.
Next thing i smelt an aweful burning smell and i pretty quickly realised what was happening. Dont know what i had turned teh volts up to, but the card seems to have survived. :clap:

[dinos22]

Yeah lol, i turned off pretty quick ;)

In addition to that, I almost burnt the card last night, straight after writing a drunken post on i4 i started playing with the volts, not realising my probe was in the vCore (CPU) read not vGPU. Kept turning and wondering why my volts werent budging.
Next thing i smelt an aweful burning smell and i pretty quickly realised what was happening. Dont know what i had turned teh volts up to, but the card seems to have survived. :clap:

that is amazing

what cooling was on it

[T_M]

Almost empty DICE (with no acetone) at about 0C.
I was idling waiting for LN2 on CPU to pull down.

[dinos22]

lucky it wasn't air cooled

how the heck did it survive such a spike
WOW MAN

you just gave hipro ideas i think :D
watches him bench at 1.8V now :rofl:

[T_M]

Given the burning smell, i'd say at least something was damaged.
Maybe i burned a phase of the power supply circuit?
But teh card still runs, havent benched it though.

[Hazaro]

Bump for more details/confirmation/numbers on the GT OVP mod.

[Hazaro]

http://www.xtremesystems.org/forums/showpost.php?p=2559731&postcount=276


I set the OVP resistance stepwise down to 2,7k.
At 3,6k the GPU core droped down from 1,3V to 1,05V idle without changing the GPU core resistance .
After setting 1,3V GPU core like before, it still shuts off.
I turned the OVP resistance down to 2,7k and the core voltage droped down to 0,95V.
Set it again to 1,3V and got still a shut off.


I think we are wrong with this resistor for the OVP mod.
We need that ..... datasheet.

Anymore info from anyone, or has everyone just gone into the main thread?

[Alexxx650]

http://www.xtremesystems.org/forums/showpost.php?p=2559731&postcount=276



Anymore info from anyone, or has everyone just gone into the main thread?
+1 my OVP Mod not work on my 8800Ulrta :shrug: Help.
and BIG Vdoop - 0.095 :mad:

[T_M]

Alex, does your resistance across the OVP resistor read constant value? Or always changing?

[hipro5]

Ohhhh.......C'mon you guys.......!...... :D .....Who's gonna solder extra coils in parallel with the existing ones so to avoid the BIG Vdroop of it and then test it in real?.....
ONLY thing you need, is to unsolder some coils from an old motherboard and then solder them onto the VGA with a lot of heatage on the soldering iron..... ;)

[Alexxx650]

hipro5 The purchase of the coil also I shall try to make this mod.
Get some .68uH at 25A+ each (at 25*C)..... This you can be put?

[hipro5]

hipro5 The purchase of the coil also I shall try to make this mod.
Get some .68uH at 25A+ each (at 25*C)..... This you can be put?

Yes.......ALSO if you don't mind, solder a couple of electolytic capacitors in parallel with the ceramic ones.....2200uF/6.3V whould be fine.... ;)

[T_M]

hipro, i'll give it a go.
Can i use the caps and R47 coils from a P5B Deluxe?

http://www.pcinlife.com/article_photo/x6800/asus_p5b_deluxe_wifi_ap/asus_p5b_deluxe_wifi_ap_1.03g-01.jpg

onto

http://www.ixbt.com/video3/images/ref/gf8800u-scan-front.jpg

[hipro5]

hipro, i'll give it a go.
Can i use the caps and R47 coils from a P5B Deluxe?

http://www.pcinlife.com/article_photo/x6800/asus_p5b_deluxe_wifi_ap/asus_p5b_deluxe_wifi_ap_1.03g-01.jpg

onto

http://www.ixbt.com/video3/images/ref/gf8800u-scan-front.jpg


Links don't work...... :(

Yes you could use them..... ;)

[Alexxx650]

Yes.......ALSO if you don't mind, solder a couple of electolytic capacitors in parallel with the ceramic ones.....2200uF/6.3V whould be fine.... ;)

Many thanks for answers and your help. :up:

http://img148.imageshack.us/img148/9143/7831998126018432wa4.th.jpg (http://img148.imageshack.us/my.php?image=7831998126018432wa4.jpg)
water

[T_M]

For anyone interested in performing hipro's vGPU smoothing mods, here's a confirmed correct diagram of how to achieve it

http://img.photobucket.com/albums/v310/T_M/gf8800u-scan-front.jpg

The caps need to be electrolytic 1500, 2200 or 3300 uF with the '-' terminal on the ground side of the SMD cap, and the '+' terminal on the vGPU side.

The coils should be from an old mobo and just soldered across the existing ones.

[hipro5]

Thanks T_M for the help...... :)

[wittekakker]

Tried the caps couple weeks ago, not of great use, no better overclock or higher benchable voltage. It's the coil that needs a mod. 'Any coil' will not help, you need right value's.

[T_M]

Darn, and i was about to do the mods with 'any values'.
So, what do i need?

[hipro5]

Darn, and i was about to do the mods with 'any values'.
So, what do i need?

'any values' from 0.47uH to 0.82uH...You can put even a 1uH.....:D

[T_M]

Hmmm, i went to an electronics shop and they had a box full of unlabelled ones.
So i just grabbed a handful of them and a handful of 2200uF 6.3V electrolytics.

Is it the size that determines the value? If so from a photo could you say if OK or not?

http://img.photobucket.com/albums/v310/T_M/Picture0011.jpg

http://img.photobucket.com/albums/v310/T_M/Picture0021.jpg

[7499richard]

going to do this now that there is a picture!!!

GREAT JOB GUYS!

[dinos22]

T_M what will those mods achieve for you

[T_M]

Higher GPU clocks

[dinos22]

Higher GPU clocks

i meant electronics wise

is that part of the OVP mod?

[T_M]

SO I think that this is the cause to work properly the OVP Mod.....One resistor is the "start up" voltage and the other resistors "tracks" the "spikes" during runing.....So if a "spike" of Core Voltage is high, the VGA powers down.....
During Vdroop (running a 3D), the VGPU NOT only goes down BUT produces HIGH "spikes" as well during a "relaxed scene" of the 3D.....
That's the reason that it worked perfect for me......


solder extra coils in parallel with the existing ones so to avoid the BIG Vdroop of it and then test it in real?.....
ONLY thing you need, is to unsolder some coils from an old motherboard and then solder them onto the VGA with a lot of heatage on the soldering iron..... ;)


For anyone interested in performing hipro's vGPU smoothing mods, here's a confirmed correct diagram of how to achieve it

http://img.photobucket.com/albums/v310/T_M/gf8800u-scan-front.jpg

The caps need to be electrolytic 1500, 2200 or 3300 uF with the '-' terminal on the ground side of the SMD cap, and the '+' terminal on the vGPU side.

The coils should be from an old mobo and just soldered across the existing ones.

Just incase you missed it.
It seems it should be performed in conjuction with the OVP mod to gain any real benefits.

[dinos22]

cool

[hipro5]

T_M I think that these coils are a bit HIGH in uH.... and LOW in current...
Also are these caps with low ESR or you just bought what this shop had?.... :(
Why don't you try what I've told you?.....Find an old motherboard and unsolder them...There you will definatelly find HIGH current coils with low uHs and LOW ESR caps.... :)

[T_M]

Because here in Singapore an "old" mobo costs ~USD$40, and all my dead/surplus boards use solids.
Guess i'll just have to go on an old/dead mobo hunt....

How can you tell about the chokes being high in uH, is it the wire thickness?

[hipro5]

Find an old ABIT IC7 or ASUS P4C800 series......They are GOOD....PLUS IC7 has the BEST Electrolytic caps Rubicom..... ;)

Chokes (Coils) MUST be a bit bigher then the ones you have and MUST have THREE coils in parallel rounded on the ferrite core (about 5 - 6 rounds)..... ;)

[T_M]

Oh i see now, when i look back at your picture.
Its 3 wires that are looped on yours. OK mate i'll keep looking.

[T_M]

Will these do the trick?
Pretty sure its what im after so ill start harvesting.

http://img.photobucket.com/albums/v310/T_M/MSIboard.jpg

http://img.photobucket.com/albums/v310/T_M/MSIboard2.jpg

[hipro5]

They are just........PERFECT....... ;) :D

[T_M]

Awesome, any tips then on how to remove them?
I know i need a lot of heat, but what technique?
Heat the underside or the topside?

[T_M]

Wow, that was easier than i thought it would be.
60W soldering iron and a little gentle persuasion:

http://img.photobucket.com/albums/v310/T_M/Picture001-1.jpg

http://img.photobucket.com/albums/v310/T_M/Picture002-1.jpg

http://img.photobucket.com/albums/v310/T_M/Picture003-1.jpg

http://img.photobucket.com/albums/v310/T_M/Picture004-1.jpg

[hipro5]

Heh, heh, heh......You're moving perfect.... :D

[T_M]

I wouldnt call my soldering skills perfect, i had a hard time getting the solder to stick to the existing inductors, but i think i've managed:

http://img.photobucket.com/albums/v310/T_M/Picture006-1.jpg

http://img.photobucket.com/albums/v310/T_M/Picture008-1.jpg

Looks like my Ultra has two dicks hehehe

[T_M]

The card is now running on water, no problems there but im still seeing 0.05V+ vdroop in ATItool, and 0.38V at worst point in Firefly '06.

[N1ck R1mer]

http://www.xtremesystems.org/forums/showpost.php?p=2559731&postcount=276
Anymore info from anyone, or has everyone just gone into the main thread?

Absolutely the same thing with my Leadtek 8800GTS - OVP Mod is NOT WORKING with GTS :brick:
Replacing the 70b resistor with 4,7 KOhm lowers Vgpu, and after adjusting it to the same level (1,45 Vgpu (2D)) it causes blank screen in HL2 Episode Two again with Vgpu drop to 0.


my dfi p965 has the primarion 3539!!!I've searched a little and found another datasheet from other company which makes the excact same chip and i have the full datasheet from that!3539 has a pin named vr_ready and i came in conclusion that this must controll the vdroop!!

If you have 3539 datasheet, please post it! :help:

[hipro5]

The card is now running on water, no problems there but im still seeing 0.05V+ vdroop in ATItool, and 0.38V at worst point in Firefly '06.

Measure with a multimeter to be sure after on the coils you have soldered and on the side of them which is to the Core.... :)
Also do the OVP Mod.... :)

Next time when soldering, use some soldering paste to "smooth" your solderings.... :)

[T_M]

Just measured each coil on the core side, and from bottom to top i read:
1.628V, 1.625V, 1.615V, 1.615V

My vCore read point on back of card reads: 1.615V

Will attach my OVP mod and see if there is a change to droop.
BTW my droop is 0.08V in 3d01!

[T_M]

Having a lot of troubles with driver corruptions and such, but as far as i can tell so far, when i connect the OVP ground i end up with vdrop (not droop) of about 0.1V.
Is that supposed to happen?

Note that i still cannot get 5.1K on the OVP resistor.
As soon as i trim down past about 5.8K it will suddenly jump to 4.2K and keep going down.

[hipro5]

Leave it at 4.2K and test it there to see how it will react.... :)

[T_M]

But do you think it's safe to operate if i'm seeing such a large vdrop (not droop)?

[Alexxx650]

dinos22 & hipro5 & T_M
All show the drawings a drawing, on which 4 capacitors, but beside all cost stand whole 2. why?
That will give if put only 4 capacitors? value has not found.

[T_M]

I only put 2 capacitors because thats what Hipro did.
If it will help, i can solder on 2 more.

Here's Hipro's: http://www.hipro-tech.com/images/hipro5/ASUS_Striker/8800Ultra_moded

[Hazaro]

I only put 2 capacitors because thats what Hipro did.
If it will help, i can solder on 2 more.

Here's Hipro's: http://www.hipro-tech.com/images/hipro5/ASUS_Striker/8800Ultra_moded

Forgot your .jpg ending ;)

http://www.hipro-tech.com/images/hipro5/ASUS_Striker/8800Ultra_moded.jpg

[hipro5]

I only put 2 capacitors because thats what Hipro did.
If it will help, i can solder on 2 more.

Here's Hipro's: http://www.hipro-tech.com/images/hipro5/ASUS_Striker/8800Ultra_moded

DID you put HEATSINKS ON VGPU's tiny Mos-Fets?.....Coz the hoter they get, their charasteristics change......Heatsinks ON them, is a MUST..... :)

IF you play with subzero, you don't need heatsinks on ram chips (better put on them too but not that much needed) BUT on the Power Mos-Fets you deffinately NEED....

[Alexxx650]

Want to put only 4 capacitors. I this will help? Or no?

[T_M]

Tested again attaching my OVP mod.
While running i grounded it and that cause a 0.04V boost to vGPU while idling.
Then i rebooted and suffered 0.1+V vdrop and the system wouldn't load windows.

[nfm]

Would any of these work?
http://img254.imageshack.us/img254/2452/p1040202xc3.jpg

I would like to try this on a 8800GT*, the OVP mod did not work for me http://www.xtremesystems.org/forums/showpost.php?p=2616073&postcount=402

[T_M]

If those caps came off a motherboard then they should no problem.
The coil is no good from what ive been told.

[N1ck R1mer]

If those caps came off a motherboard then they should no problem.
The coil is no good from what ive been told.

http://www.xtremesystems.org/forums/showpost.php?p=2594366&postcount=2340

P.S. B.T.W., I've made the Vdroop mod for my GTS:

http://www.xtremesystems.org/forums/showpost.php?p=2604174&postcount=239


I would like to try this on a 8800GT*, the OVP mod did not work for me http://www.xtremesystems.org/forums/showpost.php?p=2616073&postcount=402

There is one interesting idea, but still not enough time for that:

http://www.xtremesystems.org/forums/showthread.php?t=123046&page=10

[nfm]

Great work N1ck R1mer :up: I appreciate all of your help. I will hold off on the coils, the caps come off A P4 mobo so they should be good. I will try to find the resitors you removed from your GTS. I'm still in process of digesting all of the info. I hope shamino will speak up.

Nonetheless this is a great news to me ;)

This would be the spot to solder caps on 8800GT right?
http://img132.imageshack.us/img132/8330/capmodmn7.jpg

Edit: So I have to remove 3 (or 2 resistors) from my card to disable OCP since it kicks earlier than OVP, and then try lowering the OVP resistor from 5.2K to 4.7K or lower? I have hard time figuring out what resistors I should remove http://www.xtremesystems.org/forums/showpost.php?p=2524285&postcount=65

[N1ck R1mer]

Great work N1ck R1mer :up: I appreciate all of your help. I will hold off on the coils, the caps come off A P4 mobo so they should be good. I will try to find the resitors you removed from your GTS.

There are two of them at GT, connected to the same primarion pins. If you remove them, it could disable Vdroop, but not the OCP. I dont't have the GT card, so I cant't check this out. Is there any Vdroop on GT w/o any mods? :shrug:



This would be the spot to solder caps on 8800GT right?

Yepp, right.



Edit: So I have to remove 3 (or 2 resistors) from my card to disable OCP since it kicks earlier than OVP, and then try lowering the OVP resistor from 5.2K to 4.7K or lower? I have hard time figuring out what resistors I should remove

No, I don't know for sure how to disable OCP. The idea is to solder parallel resistors (3 for GTS, 2 for GT) to those capacitors located near the resistors that I removed.

The results of lowering OVP resistor (70b) from 5.2 to 4.7 K are:
1. Vgpu decreases (about 0.1 V)
2. OVP should work at higher voltage than with the stock 70b resistors. Practically point 2 is useless with GTS & GT, cause OCP still works earlier than OVP.

[T_M]

Nick, when i tried the OVP mod on my Ultra i thought i'd done it wrong because vGPU was suddenly 0.1V less than before. Are you actually meaning to say that means my mod was successful?

[nfm]

Nick, when i tried the OVP mod on my Ultra i thought i'd done it wrong because vGPU was suddenly 0.1V less than before. Are you actually meaning to say that means my mod was successful?
I noticed same exact thing, 0.1v less (I had to go down from 5.2K to 4.3K to notice the drop, 4.7-4.9K did nothing)
The 8800GT actually overvolts 0.05 to 0.07v at stock.

Edit: I just did the cap mod, so far so good.
http://img90.imageshack.us/img90/6805/capmodse4.jpg

[T_M]

8800GTS 512Mb overvolts about the same at stock as well, however the higher you adjust vGPU, the larger the overvoltage under load ;)
So watch out!

[N1ck R1mer]

Nick, when i tried the OVP mod on my Ultra i thought i'd done it wrong because vGPU was suddenly 0.1V less than before. Are you actually meaning to say that means my mod was successful?

Don't know about Ultra, the resistor for OVP has another default resistance value than 70b at GT/GTS. But I'm sure that OVP mod is very useful with GTX.


Edit: I just did the cap mod, so far so good.

Are you sure about polarity? :confused: The "minus" (- - -) cap pin should be on the ground. As I see on the pic, it's right, but for sure...
BTW, soldering is pretty acurate :)

PS Chemicon KZG caps are nice, Low-ESR (1500x6,3 - about 26 MOhm). Not the best, but nice.
http://www.chemi-con.co.jp/pdf/catalog/al-e1001h/al-kzg-e-070821.pdf

[nfm]

I removed the corresponding resistors on my GT to disable the overvoltage. Card still overvolted but guess what Nick? Card does not shot down anymore no matter what voltage. I did some preliminary testing upping card to 1.6v in 3DMark and 1.5v in Crysis. I ran 3DMark06 at 918Mhz and played Crysis at 900Mhz!

Let my need for mhz begin :worship:

[Hazaro]

I removed the corresponding resistors on my GT to disable the overvoltage. Card still overvolted but guess what Nick? Card does not shot down anymore no matter what voltage. I did some preliminary testing upping card to 1.6v in 3DMark and 1.5v in Crysis. I ran 3DMark06 at 918Mhz and played Crysis at 900Mhz!

Let my need for mhz begin :worship:

Which resistors would that be :D

[T_M]

NFM, do you mean that your overvoltage value is now your normal volts?

[nfm]

Not exactly, card still overvolts. At 1.50v idle it overvolts close to 1.60v (firefly 3dmark06). Looks like OVP does not exist on 8800GT :confused: , once you disable OCP through removal of two resistors, card will never shut down.
http://img264.imageshack.us/img264/4826/8800gtocpxa2.jpg
These are same resistors (x78 value) nick removed from a gts, and his effect was no more vdroop.

[dinos22]

I removed the corresponding resistors on my GT to disable the overvoltage. Card still overvolted but guess what Nick? Card does not shot down anymore no matter what voltage. I did some preliminary testing upping card to 1.6v in 3DMark and 1.5v in Crysis. I ran 3DMark06 at 918Mhz and played Crysis at 900Mhz!

Let my need for mhz begin :worship:


Not exactly, card still overvolts. At 1.50v idle it overvolts close to 1.60v (firefly 3dmark06). Looks like OVP does not exist on 8800GT :confused: , once you disable OCP through removal of two resistors, card will never shut down.
http://img264.imageshack.us/img264/4826/8800gtocpxa2.jpg
These are same resistors (x78 value) nick removed from a gts, and his effect was no more vdroop.

OMG you just figured out the OVP mod

that was easy :D:D:D:D:D::D:D :up: :up: :up: :up:

[Timbosan]

N1ck removed the '70B' resistors, you have removed 2 '70X' resistors. Can you tell me what pins of the PX3544 chip that have continuity to the 2 resistors you removed? It looks like the top resistor joined point 1 in my pic and the second side resistor joined either point 2 or 3.

[Hypertek]

Not exactly, card still overvolts. At 1.50v idle it overvolts close to 1.60v (firefly 3dmark06). Looks like OVP does not exist on 8800GT :confused: , once you disable OCP through removal of two resistors, card will never shut down.
http://img264.imageshack.us/img264/4826/8800gtocpxa2.jpg
These are same resistors (x78 value) nick removed from a gts, and his effect was no more vdroop.

so to get this straight im tryin to understand.. you unsoldered those 2 resistors, and now you can basically up the voltage/overclock the gpu to your hearts desires? (of course withen the limits of what the gpu can handle til it craps out)

[N1ck R1mer]

N1ck removed the '70B' resistors, you have removed 2 '70X' resistors.

No, I've replaced ONE 70b (5,22 K) resistor (it connected to Vmax Primarion pin) with the 4,7 K (first with 5,1 K) to get rid of the OVP, but OCP still works. I've tried to disable OCP, so I removed that three '78X' resistors, but the effect was unexpected (I only discovered the Vdroop mod as a result).


I removed the corresponding resistors on my GT to disable the overvoltage. Card still overvolted but guess what Nick? Card does not shot down anymore no matter what voltage. I did some preliminary testing upping card to 1.6v in 3DMark and 1.5v in Crysis. I ran 3DMark06 at 918Mhz and played Crysis at 900Mhz! Let my need for mhz begin :worship:

I'm glad to hear that! The resistors you removed definetly belongs to the current control scheme, so my first objective was to disable OCP.

[Timbosan]

right my bad sorry. i was at work, my mind was somewhere else & i got the ocp & ovp mods confused :p:

[nfm]

Is it technically possible to remove overvoltage on my 8800GT? BTW I did not do OVP, it's at original 5.2K. If you guys (Nick, T_M or Timbosan) have any ideas on unsoldering few things let me know ;)

@Timbosan
I do not know how to check the continuity :yawn:

[Timbosan]

i think the OVP mod would be one of these 2 resistors i identified with the pink square. What are the 2 resistors resistances?

to check continuity you set the dmm to the 'diode' setting, it looks like an arrow with a line through it near the head. alternatively you could set it to resistance and see if there is a zero resistance connection.

[nfm]

I wasn't sure which points, I sticked it to where I unsoldered the resistors, top showed 1.22 and bottom 0.53 (according to the pic)
70B is the OVP for 8800GT, but that adjacent 63B resistor looks interesting :D .

[N1ck R1mer]

i think the OVP mod would be one of these 2 resistors i identified with the pink square. What are the 2 resistors resistances?

Hey! I'm not gonna repeat what I said once (http://www.xtremesystems.org/forums/showpost.php?p=2624192&postcount=168). There is ONLY ONE Vmax Primarion pin.

[Timbosan]

yeah i know the 70b is ovp resistor & connects to vmax pin. we sorted it via PM i thought he meant something else - to remove ovp completely (as he has performed the ocp mod the only limitation is voltage) I thought he wanted to unsolder the resistor - so i wanted to see what it had continuity with to see if that would cause trouble.

[hehee]

i've problem of card shutdown when i do anything over core 710mhz.vmod at 1.45...
is anyway to remove few resistor for GTX to disable OVP...?

[Timbosan]

i've problem of card shutdown when i do anything over core 710mhz.vmod at 1.45...
is anyway to remove few resistor for GTX to disable OVP...?

The GTX OVP mod is post 1 of this thread :)

http://www.xtremesystems.org/forums/showthread.php?t=162124

[hehee]

The GTX OVP mod is post 1 of this thread :)

http://www.xtremesystems.org/forums/showthread.php?t=162124

i've no luck for my GTX...1st batch...
get frezee anything above core =695mhz
no effect from 1.5v to 1.6v
dun dare put above 1.6 cause on water only

mem also limit to 1035 not much effect on mem vmod....
i guess OVP not for me ....

btw is anything overclocking protection for GTX ?anyone can answer this...?

[N1ck R1mer]

hehee, if you are using stock, you shoud try a better cooler, - Thermalright for ex.

[hehee]

hehee, if you are using stock, you shoud try a better cooler, - Thermalright for ex.

on water now...temp never more than 56c

i mod the 4x rubycon 6.3v 1500uf but not the coil yet...
anyway i tried OVP ...no luck still kick in bout 1.6v

[N1ck R1mer]

i mod the 4x rubycon 6.3v 1500uf but not the coil yet...

http://www.xtremesystems.org/forums/showpost.php?p=2594366&postcount=234



anyway i tried OVP ...no luck still kick in bout 1.6v

This is OCP, not OVP.

[by -=Merlin=-]

I noticed same exact thing, 0.1v less (I had to go down from 5.2K to 4.3K to notice the drop, 4.7-4.9K did nothing)
The 8800GT actually overvolts 0.05 to 0.07v at stock.

Edit: I just did the cap mod, so far so good.
http://img90.imageshack.us/img90/6805/capmodse4.jpg

8800GT


What brings the benefits, Please For detailed statement.

Merlin

[winbond]

8800GT


What brings the benefits, Please For detailed statement.

Merlin


yeah i'd like to know too what's the point of adding those and whats your overclock on the card? thanks

[Timbosan]

adding the caps in parallel to the existing caps provides extra filtering of the gpu voltage. However this only comes into play at voltages above ~1.5v. Adding the coils im doubtful would help at all. Adding the caps (& coils) wont give you a better overclock alone, but are meant as a supporting mod to assist running high (1.5v +) gpu voltages.

[wittekakker]

True, this can and has be done for many other hardware in the past, still it is not the best way to get rid of OCP.

[hehee]

I've moded 4 caps only helps the cpu overclock ...
b4 the vcore of cpu wasn,t stable jumping between 1.488-1.502...
after i put on caps mod it stable at 1.488
it benefit my Q6600 from 3.6 to 3.85 stable now.
but not helping for gpu overclock....
weird...

[VoRtAn_MaDgE]

So for 8800gt/gts g92 mod's the same?
Little bit confused with so many pics :rofl: ...
Ocp makes the vga no longer "shuts" down ???

Clear pics would be great

OCP for 8800gt/gts g92 this one?
http://img264.imageshack.us/img264/4826/8800gtocpxa2.jpg

Ovp no luck so far correct?

[Timbosan]

Ovp no luck so far correct?

OVP has been done (read first few pages of the thread). Here:

[VoRtAn_MaDgE]

Possible to prevent the card from the shut off without taking the resistor off?
Can we add a vr at one side of the smd and adjusting the pot to neutralize the value ?
Or maybe pencil mod for ovp

[jmax_oc]

OVP works at home (1.62V burn OK). But OCP doesn't work (last explosion for Aquamark is the best test for it).

Any idea for OCP removal ?

[VoRtAn_MaDgE]

OVP works at home (1.62V burn OK). But OCP doesn't work (last explosion for Aquamark is the best test for it).

Any idea for OCP removal ?

http://www.xtremesystems.org/forums/attachment.php?attachmentid=69589&stc=1&d=1198824594

Removed, add a pot or penciled the bastard ? :D

:up:

[jmax_oc]

Hmm, to cancel OCP, do I have to unsolder the 2 little resistor surrounded ?

[aussie-revhead]

Sorry for nub question guys but do these work with G92 GTS also ? Is there a thread on my card ? What is the difference between OCP and OVP ? Which do I need on a water cooled card ?

Any help would be great.

:up:

[jmax_oc]

Up : how to cancel OCP on Primarion 3544 controller ? 8800GT for me.

[janos666]

I have an old A2 8800GTS-320. I tryed to pencil the assigned resistor (post #7). I lowered the resistance to 4,75 KOhm as you said. My default VGPU falled back with ~0,1 V. I started to turn down my soldered resistor (for VGPU mod...) until 1,45 VGPU and gained some extra Mhz but OVP (or OCP, I do not know what is the correct word) turned down my card during 3DMark.

Does anybody tryed it with success? Which is the good resistor and resistance value?

[largon]

janos666,
It's possible your card is tripping due to OCP.
G80 OCP mod can be found here (http://www.xtremesystems.org/forums/showthread.php?t=171016).


Up : how to cancel OCP on Primarion 3544 controller ? 8800GT for me.You need to solder some SMRs on couple of SMCs.
->
http://www.xtremesystems.org/forums/showpost.php?p=2700699&postcount=546
Basically it's the same as G80 OCP mod. Just different locations.

[EL RICHARDO]

For anyone interested in performing hipro's vGPU smoothing mods, here's a confirmed correct diagram of how to achieve it

http://img.photobucket.com/albums/v310/T_M/gf8800u-scan-front.jpg

The caps need to be electrolytic 1500, 2200 or 3300 uF with the '-' terminal on the ground side of the SMD cap, and the '+' terminal on the vGPU side.

The coils should be from an old mobo and just soldered across the existing ones.Where is the negative/positive? :confused:

[T_M]

as per PM, measure which side of the SMC is grounded and attach the negative to that.

[Benji Tshi]

Hi,

There is a lot of different ovp mod, i'm not sure that every one works perfcectly.
Did anyone find it and can set 1.6v on gpu ?
I need it, LN2 is coming last week so i don't want to be stuck at 1.4v.:p: Please help me!

Thanks ;)

[T_M]

I never had any luck in raising OVP

[Benji Tshi]

So how do you get 1.1Ghz + on a GTS 512 ?

[T_M]

cold and volts, manage your OCP

[quake6]

Could someone pt vmods for 8800gtx? Thanks

[T_M]

Search

[chew*]

Search

Yep search works, just finished VGPU, cap/choke mod, OVP and OCP :up:

Cards begging for ln2.

Now i just need to find a way to undervolt these crap quimondas.

http://chew.ln2cooling.com/The_Laboratory/3d05%20single%208800gt%203.jpg

[CL3P20]

I should try on my GS... hitting limits around 1060 core right now. Inductor mod allows 1.43v before OCP... but I need a tad more. :D

http://hwbot.org/community/submission/988470_cl3p20_aquamark_geforce_8800_gs_384_mb_2933 52_marks
http://i265.photobucket.com/albums/ii220/CL3P20/OCN%20post%20pics/293k_am3.jpg

[KanGaXx]

Did you expected it?.......Get it......THAT simple and as promised......:D

This picture includes the VGPU and the OVP of the 8800GTX and 8800 Ultra VGAs......8800GTS is SIMILAR but in anoter position of the PCB......;)

CREDITS for the VGPU Mod goes to Shamino and vr-zone.....;)

http://www.hipro-tech.com/images/hipro5/NVIDIA_8800_Mods/8800_VGPU_OVP_Mods.jpg


Here is the OVP Mod in a closer look.....:)


http://www.hipro-tech.com/images/hipro5/NVIDIA_8800_Mods/8800_OVP_Mod_1.jpg


......and here's an alternative method for more "hardcore" people.....:D :p:


http://www.hipro-tech.com/images/hipro5/NVIDIA_8800_Mods/8800_OVP_Mod_2a.jpg

http://www.hipro-tech.com/images/hipro5/NVIDIA_8800_Mods/8800_OVP_Mod_2b.jpg


By doing so, you will NOT ENCODE this f(l)uken VGA's shut down and core powering down problem any more..... ;)
You'll ONLY have to deal of how much VGPU you will feed it until it produses Core artifacts during a bench....
IF you get a "freezing" during a bench, then your VGA's core CAN'T go higher than that...... :D :p:

Happy NVIDIA VGA Overclocking and DON'T pass my scores..... :D :p:


.


anyone one have those images ??

some good people :)

[K404]

Tin_EOF has a thread with pics :)

I'm... feeling too lazy to go a-hunting though, sorry :)


IMHO only OCP mod is really necessary. Caps got me more voltage to the core, but no extra MHz or stability

[KanGaXx]

yes, the problem is that i have not understand the OCP mod...

i have those:


here i have to replace the 70B with a 472.
i have to parallel solder 122 on the capacitors near the 78X.
I have to remove the 78X ??? ( red ones )
http://www.pctunerup.com/up/results/_201008/20100818121054_141832.jpg


here the 78X are removed it's right ?
what is the white wire circled (red) ???
http://www.pctunerup.com/up/results/_201008/20100818121054_145278.jpg

[K404]

For the OCP mods, measure the basic resistance across each capacitor (the components next to the red ones in the first pic you posted) and solder a resistor of equal or slightly larger value in parallel. This will increase your OCP limit significantly :)


The 2nd pic with the red circle..... Thats the mod point for the vCore but I have NO idea why the wire is going to a diode. It should go to a 1K trimmer (other end connected to ground)... nice and simple :)

[KanGaXx]

the reds resistors on the first pics should be removed???

[K404]

Nope :) Or at least.... I didn't remove them (dont think Tin did either) and I was happy with the MHz I got

[KanGaXx]

i asked that because (in the second picture) they are removed.


that's ok ?

http://www.pctunerup.com/up/results/_201008/20100818124936_141832.jpg

[K404]

I have no idea what effect that would have, sorry.

As it happens, I might be benching a 320MB today. I have the OCP mods done, i'll let you know how it goes, if I get it done :)

[KanGaXx]

good good :) i want bench it too :D

so, it's ok the pic i have posted above ? the parallel is right ?

[K404]

Yea bro :) perfect

[Calathea]

Thats the mod point for the vCore but I have NO idea why the wire is going to a diode. It should go to a 1K trimmer (other end connected to ground)... nice and simple :)

Look closer, it's a 1000 Ohm resistor. Probably someone were happy with that slight boost to vCore :shrug: (Assuming GND on the other side of resistor)

[K404]

Great catch! Yea... my bad. I should have noticed the SMC wasn't "going anywhere"

[KanGaXx]

i have an 1R0 smoking :/
i have removed it, i can replace it with an inductor of a dead board ?

[Calathea]

I would try to find another 1R0 (1.0 uHenry) inductor. Maybe 1R2 or R80 can work, I don't know how precise the value must be.

[tigeredwards]

very good