8800GT voltage mods

[4Qman]

Just got a BFG 8800GT from best buy right now $250 on sale. Expect it to be volt modded soon.

Do I have to get a Multimeter or can I just put on the 1k ohm 15 turn potentiometer straight on? The screw is how it came inside the package from radioshack.

as Largon has said getting a metter is a very very wise investment,. After all im sure you use it again and again.

Oh and id NEVER put a VR without checking its resistance on anything. A friend did it once and killed his 7800GTX back when they were Stonking cards.

[96redformula]

96redformula7,
There's no way to know what vGPU you end up with without a DMM.
Besides, a DMM is very useful in general.

Would a radio shack multimeter be alright? I am very tight on cash, thanks for all the help guys. I will have it watercooled too, so I am looking for some good results .

[Hazaro]

Would a radio shack multimeter be alright? I am very tight on cash, thanks for all the help guys. I will have it watercooled too, so I am looking for some good results .

I asked on OCF
http://www.ocforums.com/showthread.php?t=535450

I'm looking to pick up a $20 DMM from Sears since I would think Craftsman > Radioshack.

[Renegade5399]

I have a fluke, 2 radioshack, and some pocket sized cheapy. And when it comes to measuring voltage and resistance, they all work the same.

[Spideroz]

Hi guys, first i want to say thank you for the Vmod who works perfectly.
I realised the Vmodd two weeks ago, and everything works great, my twintech 8800 Gt run @ 850/1000 with a Vgpu : 1.36V
I’m a little bit surprised when I see so many problems with the ovp.
I have no issues with the card at 1.36V and I can easily push The Vcore over 1.4V without any problems, black screens or reboot.
My 8800 Gt is watercooled; I put little radiators on the VRM and an 80mm fan on top of them.

Because all the first 8800 Gt are the same, and got the reference design of NVIDIA’s cards, I don’t understand why so many peoples have problems to run the card with a Vgpu over 1.35V?

Here is some screen:

-8800Gt@850/1000 Vcore 1.36V idle, 1.41V full

Voltmeter picture@1.41V
http://img441.imageshack.us/img441/1...41vfulljz0.jpg

30 min Ati tool picture@ 1.41V
http://img529.imageshack.us/img529/3...ol31minzq4.jpg


-8800GT@850/1000 Vcore 1.41 idle, 1.46V full

Voltmeter picture@1.46V
http://img143.imageshack.us/img143/6...146fullny6.jpg

8 min Ati tool picture@ 1.46V
http://img239.imageshack.us/img239/3...ool8minir2.jpg


-My best 3D mark 06 score, 8800Gt@850/1000 Vcore 1.36V full, over 860 MHz for the Gpu my score decrease, even with more volts.




With my Vcore@ 1.46V I tried to play four hours at call of duty 4 and three hours at crysis, and I everything works great, no reboot, no black screen and my maximum temp are 43° Celsius for the core and 35° for the card.

Am I just lucky with this card?? I don’t get it

I have a last question; I would like to know if a software is able to monitor the Vgpu of the 8800 Gt under windows Xp??

[JKDC]

Is 850/2125 as far as it will go at 1.46? I am maxing out at 810/2000 on air at 68C in Crysis with 1.34v load. I think that is as high as it will go on air. Crysis still runs like S*** too, mid 20's on level 3 and 4 so far even at 720p, With a Q6600 @ 3.2, but it looks like it only uses 1 core according to my G15.

[Spideroz]

No, at 1.46V for the Gpu, i can push the card at 880mhz, and reach 900mhz if i lock the shaders at 2100mhz.
but my performance decrease when the gpu run over 860mhz, so i set the card on 850/1000, i reach my best scores with this settings.
So Actually my card run at 850/1000 Vgpu: 1.36V full since the last two weeks

[JKDC]

My score lowers too over 810 core even though it is fairly stable. I guess we maxxed out the GPU. So are you going to get a G92 8800GTS in 2-3 weeks? I'm debating it...it should have the same PCB and same vmod but I might wait and get the GX2. That is 1.36v idle right?

[Hazaro]

Got my Sears DMM for $20 and gel superglue, waiting for the circuit writer to get to me (Hopefully before Thursday!).

Set my VR from RadioShack to 500 ohms. It was at 550, half a turn counter-clockwise = - 33 ohms, so 3/4 a turn later I get 498 ohms!

Can't wait

Shame my E6600 can only do 3.4 under crazy volts.

[96redformula]

After all this talk about the Vmod I am not sure I am going to go through with it.

I was maxing out earlier due to heat @ 756 on the GPU. I have since installed it into my watercooling loop which keeps it from 35C to 41C maxed out.

I am already hitting with stock bios with NO Vmod:

771 GPU
1836 Shaders

3dmark06 14600

I have still not maxed it out, but will get to it later tonight.

[r4st4m4n]

After all this talk about the Vmod I am not sure I am going to go through with it.

I was maxing out earlier due to heat @ 756 on the GPU. I have since installed it into my watercooling loop which keeps it from 35C to 41C maxed out.

I am already hitting with stock bios with NO Vmod:

771 GPU
1836 Shaders

3dmark06 14600

I have still not maxed it out, but will get to it later tonight.

http://img123.imageshack.us/img123/9...18800gtpu2.jpg

In your screenshot, the title of the rivatuner window says 8400GS and also in the 3dmark window

If you are using stock bios you might want to try the bios mod to get 1.1Vcore. You may gain few more MHz. It worked great for me.

[96redformula]

The title of the rivatuner window says 8400GS and also in the 3dmark window

It was the previous card that I had prior to the 8800GT, probably need to clean out the drivers.... I am going to do it now. I was thinking it was a glitch since the 8800gt is so new.

EDIT: Seems like some sort of glitch with rivatuner?? Everything else is correct on the computer and all previous drivers were removed.

[Hazaro]

It was the previous card that I had prior to the 8800GT, probably need to clean out the drivers.... I am going to do it now. I was thinking it was a glitch since the 8800gt is so new.

EDIT: Seems like some sort of glitch with rivatuner?? Everything else is correct on the computer and all previous drivers were removed.

Run driver cleaner and use the 169.02 or 169.09 drivers.

[96redformula]

Run driver cleaner and use the 169.02 or 169.09 drivers.

The strange thing is that I have. I think the 169.09 might have a glitch with rivatuner.

[r4st4m4n]

The strange thing is that I have. I think the 169.09 might have a glitch with rivatuner.

In the first screenshot, 3dmark also display 8400GS ... You probably have the world record 3dmark06 with a 8400GS

Maybe both software build their database at the first startup and didn't refresh the name correctly.

Just for the sake of it you may try to uninstall and install again both but as long as the performance are not the one of a 8400GS, who cares

[npk]

No, at 1.46V for the Gpu, i can push the card at 880mhz, and reach 900mhz if i lock the shaders at 2100mhz.
but my performance decrease when the gpu run over 860mhz, so i set the card on 850/1000, i reach my best scores with this settings.
So Actually my card run at 850/1000 Vgpu: 1.36V full since the last two weeks

What gpu block are you using and what ambient temps do you have? 39º running atitool is very good considering the vgpu you´re using.. and that´s a great card for sure

[dinos22]

Spideroz
pls detail your mod with pictures

maybe you are doing something different for OVP

[Pacha]

Hi guys, first i want to say thank you for the Vmod who works perfectly.
I realised the Vmodd two weeks ago, and everything works great, my twintech 8800 Gt run @ 850/1000 with a Vgpu : 1.36V
I’m a little bit surprised when I see so many problems with the ovp.
I have no issues with the card at 1.36V and I can easily push The Vcore over 1.4V without any problems, black screens or reboot.
My 8800 Gt is watercooled; I put little radiators on the VRM and an 80mm fan on top of them.

Because all the first 8800 Gt are the same, and got the reference design of NVIDIA’s cards, I don’t understand why so many peoples have problems to run the card with a Vgpu over 1.35V?

so apparently there is not much gain on vgpu freq above 1.35V full load, so not much of a big problem if the card ovp then. interesting, thanks for sharing

[Daveb2012]

Anybody want to put it in step by step terms for the Vmodd. I had done the 7900GT Vmodd in the past with a silver ink conductive pen and it worked great. Can you all put it in laments terms on what to buy and how to do it? I have both the gel superglue and the silver ink pen, so I can probably do that without taking a big chance on saudering.

I was going to wait for the 8800GTS G92, but if I can get a vmod on a 8800GT I will take that route.

Cooling: MCW60, Swiftech Ramsinks, Swiftech VReg sinks

I agree with this, I really want to try it out but until a nice guide comes along I don't have the confidence to attempt it like many of us here. I have already a soldering Iron and will give it a shot with a better write up on how to do it. Pleeeease?!

[96redformula]

I agree with this, I really want to try it out but until a nice guide comes along I don't have the confidence to attempt it like many of us here. I have already a soldering Iron and will give it a shot with a better write up on how to do it. Pleeeease?!

When you look at the 8800GT, it is much smaller than in the pictures you are seeing too. I went ahead and bought the 8800GT and will do the Vmod at a later point in time as needed.

If you are going to attempt this mod, you should practice soldering a little bit or read the soldering part in the mod section on the proper procedure for this type of mod.

Please let me know if any of these are wrong or need to be edited, I have yet to do it. Do Not Take My Word Until A More Knowledgable Person Can Confirm This!!!

Order of steps:
1.)Get all parts
2.)Measure 1k Potentiometer for correct resistance(should be about 550ohms without being adjusted, adjust for desired voltage if you get the radioshack 15 turn one, which is recommended)
3.)Solder a wire to the middle peg on the resistor
4.)Solder a wire to the end peg(peg farthest from turn screw) on the resistor
5.)Solder the wire from the end peg to the VGPU point as shown on the pictures
6.)Solder the middle peg on the resistor to the ground point as shown on the pictures
7.)Tape down the resistor to the PCB as shown on the picuture
8.)Use the points shown on the picture to check and measure the Vcore's voltage

Followed by testing and more overclocking in windows....

The guide on soldering will be helpful as to the proper way to get such small points done without messing up. Once again from my understanding you go ahead and get the wire prepped with the solder, line it up on the point at which you want it soldered, and then use the solder gun to melt the solder on the wire.

[Spideroz]

Hi guys, i'm using a WaterBlock CHIPSET NexXxoS NBX-i, and my ambient temps was 20° celsius during the test.
In my system i just have another waterblock for the cpu and both are cooled by a blacklord radiator with four 120mm fans.




it's true than over 1.36V for the Vgpu, the gain is not really interesting with my watercooling, that's why i set my card to 1.31V idle, 1.36full and reach 850/1000, it seems to be the best settings for me.


For the detail of my Vmodd, i don't have a lot of pictures, in fact, i just took one with my old camera, and the quality is pretty bad :p


For this mod i do nothing particular and i just follow this guide using a 1000ohm Vr.

[largon]

96redformula7's write-up is perfectly correct, if a bit unnecessarily complicated.

All that is needed is:
1. Solder a wire on two of the legs on a variable resistor. The other has to be the middle leg.
2. Tune the resistance between the unsoldered ends of the wires to ~500Ω.
3. Solder one wire to mod solder point (red/orange dot in the pic) and the other to a ground (any of the blue dots, eg.).
4. Done.

[96redformula]

96redformula7's write-up is perfectly correct, if a bit unnecessarily complicated.

All that is needed is:
1. Solder a wire on two of the legs on a variable resistor. The other has to be the middle leg.
2. Tune the resistance between the unsoldered ends of the wires to ~500Ω.
3. Solder one wire to mod solder point (red/orange dot in the pic) and the other to a ground (any of the blue dots, eg.).
4. Done.

I knew I would make you proud

[Fungus]

@96redformula

run rivatuner from command line with /build switch.

That should clear up the misdetection problem.

[Hazaro]

Wondering here...

Adjust VR and measure voltage while computer is on? Or do you suggest turning it off and then turning VR?