Nvidia 8800GTS Vmods

[lowfat]

I tried to do the Vmod today, it didn't go so well.

Before the vmod Vgpu was 1.26 idle and load.

Even with the resistor cranked on startup after the Vmod Vgpu was 1.65, and booted to a black screen. I removed the Vmod and it was then reading 0 voltage.

So i removed the wires to read point, installed stock cooling and all seems fine now. Very wierd.

It is a shame to as it took me forever to get my hand steady enough to make the Vgpu solder. I really don't know how you people can do it. That point is way to small.

I see on that madshrimp site it shows a pencil mode for Vgpu, anyone try it out?

[Console]

Just did this mod on my 320mb today .


Where does the OVP kick in @ .
What Vgpu and Vmem are most ppl Using

Right now im @ 1.5v gpu and 1.96v mem
675/1060
680 or 1065 wil cause it to lock up

Im on stock cooling BTW next friday I will be getting a WB for the card .

[cowie]

ovp kicks in for me anyway after @1.429 read in 3d mode,good for 700 ish
stock cooling,reseated the heatsink with as 5 and ghetto mod to fan.
same 1.4289 with some dry ice to cool ambient temps 730 ish

for stock heatsink 1.35 @load is hot to say the least,well depends if its summer or winter where you are.
but for benches i turn volts up,gamein or desktop i just turn it down.

[TiTON]

How can you tell if ovp kicks in or not?

Is there a way to disable ovp on these cards?

SAD

[cowie]

I tried to do the Vmod today, it didn't go so well.

Before the vmod Vgpu was 1.26 idle and load.

Even with the resistor cranked on startup after the Vmod Vgpu was 1.65, and booted to a black screen. I removed the Vmod and it was then reading 0 voltage.

So i removed the wires to read point, installed stock cooling and all seems fine now. Very wierd.

It is a shame to as it took me forever to get my hand steady enough to make the Vgpu solder. I really don't know how you people can do it. That point is way to small.

I see on that madshrimp site it shows a pencil mode for Vgpu, anyone try it out?

did you use 1kohm vr?even a 1k "set" to 800ohms only gave me 1.31 at load if i remember correctly
i have two of the same cards no likey after 1.429 at load,blackscreen. sheez just you had to back it down abit.try again if you must(i know i would)
much to low resistance for pencil on gpu

[cowie]

How can you tell if ovp kicks in or not?

Is there a way to disable ovp on these cards?

SAD

black screen,to be honest 1.42 is more than e-nuff for air.

[lowfat]

did you use 1kohm vr?even a 1k "set" to 800ohms only gave me 1.31 at load if i remember correctly
i have two of the same cards no likey after 1.429 at load,blackscreen. sheez just you had to back it down abit.try again if you must(i know i would)
much to low resistance for pencil on gpu

Ya i tried a 1K ohm variable resistor. IMO I think i just didnt solder to the wrong point.

I am not going to bother doing it again, it is far beyond my skills, I can barely even see the solder point even with a magnifying glass.

[ineedaname]

I tried doing the pencil mod the other day and I didn't have much success.

I can't go much higher on my card than before. I don't have a multimeter on me so I can't really see how much extra voltage I have tho.

Before pencil mod I could do 690 on the core and now I can do 700. As for the ram....

well the ram could do 1700 before the mod and is still completely stuck at 1700.

I also have recently changed from stock cooling to a HR-03 PLUS and it hasn't made any difference on the OC but its obviously helped the temps.

I'm considering doing the solder mod next weekend.

Here's my 3dmark 06 score at 700/850

http://service.futuremark.com/compare?3dm06=2599571

(it says 4ghz but its actually 3.6ghz on 8x multi)

[cowie]

this is all i could get on stock ghetto air,

guys remember to clean off area with some alcohol to remove any factory flux leftovers

[lowfat]

http://www.madshrimps.be/?action=get...194&howtoID=72

any one done the Vgpu mod shown here? It is quite a bit different from the other one shown. Looks a bit easier maybe for someone with poor soldering skills like me.

[trans am]

any one done the Vgpu mod shown here? It is quite a bit different from the other one shown. Looks a bit easier maybe for someone with poor soldering skills like me.

Im in the same boat. I'm ready to do the mod but only have 1kohm vr. they used 10k vr for the mem and 1kohm for the gpu. Anyone want to walk me through this?

1st thing should I measure the stock vgpu?
then I'm suppose to measure the resistance of the pink and red points with the card unplugged.

Then not enough resistance so start soldering?

I'm nervous. :\

how do you guys stick the vr to the corner of the pcb so neatly? Is that a glue gun? Any good place to order extra vr's online if you live in US? Thanks

For the GPU core voltage mod we must search for the Primarion PX3540 PWM IC. The resistor marked in blue is the one you need to shade with your B2 pencil. Strike it a few times and measure how the resistance changed, you can check resistance by holding the red wire of your multimeter to the red point and the black wire of your multimeter to the pink point.

The stock resistance measures around 35 Ohm, this is very low and this will make it very hard to pencil mod the GPU core voltage, we recommend doing the soldered modification. For the solder mod we used a 1kOhm adjustable resistor (often called VR) and soldered it between the red and pink point. This changed our stock voltage from 1.3V to 1.33V. To further increase voltage we must lower the resistance of the variable resistor, before you power on your system always make sure that your VR is set to highest value. For 1,4V we adjusted the stock resistance of 35 Ohm to 29 Ohm.

[Console]

I used 20k VR for both the Vmem and Vgpu . I should have used a smaller VR for the Vgpu But I just turn it very slow and i can still dial in what im looking for .

So other ppl over 1.45ish get a black screen from OVP ? i have had mine upto 1.65v and it was still working .

Im hoping to get into the 700mhz range when I get it on water

[Lord_RTKK]

I did the vGPU mod, and we came with this:

http://www.xtremesystems.org/forums/...d.php?t=152734

Not bad at all...

My dewar has just arrived, so in the upcoming weeks we will have LN2 session. We have benched this E6700 in 3D at 5.250 Mhz with LN2, so now, with LN2 again and GPU Pot with vmodded 8800GTS, the fun is assured...

Regards, Lord.

[cowie]

[QUOTE=Console;2346129]I used 20k VR for both the Vmem and Vgpu . I should have used a smaller VR for the Vgpu But I just turn it very slow and i can still dial in what im looking for .

So other ppl over 1.45ish get a black screen from OVP ? i have had mine upto 1.65v and it was still working .

Im hoping to get into the 700mhz range when I get it on water
[QUOTE=Console
well damn i run 1.42 on air at 700?
on three differant cards?(same type evga sc)

[Console]

Really ? you can run @ 700 on air with only 1.42v ! the best i can do is 676 and that is with a 92mm Tornado on the HSF .

[cowie]

yes @1.428 120mm fan bolted on stock heatsink 700 @65f room temp
and Lord RTKK(really great job bro) runs 890 @1.59 it shows that its in the cooling i think
i take my time to try and get best mix of volts and temps.

more volts is not always better...... nah nevermind it is lol

[4Qman]

i Have 1.23 IDLE and it goes to 1.21v load on my EVGA. Max clock is 636 Core any more it crashes on STOCK cooling.

Have some resistors here and a nice water block so will see if i can reach 700Core for 24/7 gaming

[wittekakker]

any one done the Vgpu mod shown here? It is quite a bit different from the other one shown. Looks a bit easier maybe for someone with poor soldering skills like me.

Working, 100% shure about it.

[4Qman]

My Evga Rev2 8800GTS 640mb card was a little bad STOCK.

Stock voltages were
1.24vIDLE 1.21v LOAD GPUCore Max clock was 625
1.76v Ram MAX CLOCK was 900Mhz


Water Results with VMods
GPU 700Core 1.41v
Ram 1000Mhz 1.84v

[Chri$ch]

Zotac 8800GTS 640MB (GPU Rev. A3)

Def. vGPU 1.31v Idle / 1.26v Load = 702/1000 stable
now vGPU 1.35v Idle / 1.30v Load = 730/1000 stable

max clock to bench 756/1050 (watercooled)

[Chri$ch]

i think with sli no problem, i had 13937 points with single gts & quadcore @ 3.7Ghz.

[afireinside]

Single card, 06 stops scaling around 3.6 on quad. SLI I have no idea, had to send the quad back

Nice bench speed Chrisch!

[Liquid69]

hey guys, im contemplating doing a vmem pencil mod, but im not exactly sure how to do this.. Ive never done a pencil mod before but I'd like to give this a go as I can only reach ~870 stable on mem whereas im reaching 685 so far on the core stock volts. I read the madshrimps vmod guide and they say to just strike the resistor a few times... So i just run a few lines across the resistor and then measure using the 2 points listed? Does the card need to be in the system when I measure these points or not? Sorry for such a noob question.

[trans am]

wow! 685 gpu is pretty sweet with no mods. very nice core on that card..

I agree your mem clock needs some work.

[Chri$ch]

hey guys, which voltage is safe for 24/7 use?

i tried 1.38v vGPU (Load / idle ~1.42v)