9800GTX voltmod thread

[Droperidolum]

Sorry, I was wrong when measured resistance between FB`s and my vDD / vDDQ points (on SMD). Now i measured on your points - on "Delta" coils.
A-vDDQ = 670 Ohm
B-vDD = 960 Ohm
C-vDD = 750 Ohm

How about vDD up/down modz?

And one more thing. When set 1.57-1.58V on GPU and burning FurMark, system hangs up and then reboots when overclocked. It also reboots when 1.62+ even @stock clocks. Temps are about 60C warm_water_cooled.
I suppose OCP/OVP mods need for cold water bech... Could you help me please?

[jackies]

Hey Droperidolum!
So what was your max stable voltage?
And maximum freq?

[Droperidolum]

Oh dear god, please make largon to answer me
please
`cause i cannot find max clock and cannot bench on cold water without ocp/ovp

[largon]

Oops, I kinda forgot this thread existed.
OCP mod should be straight forward copy-cat of 8800GT/GTS/GS OCP. The caps aren't placed identically but they're there. You might want to confirm the resistance of the caps is similar to that in the linked guide. What comes to vDD mod - try it from pad B-to-ground (VR @ 20x the stock resistance).

btw, did you try the reverse mods (in post #73)?

[Droperidolum]

Oops, I kinda forgot this thread existed.

Yeap, it existing and... dammit... i really glad to see u here again, man!

OCP mod should be straight forward copy-cat of 8800GT/GTS/GS OCP. The caps aren't placed identically but they're there. You might want to confirm the resistance of the caps is similar to that in the linked guide.

So, these four brown caps around primarion is 740 Ohm each (OMG I just measured RESISTANCE of CAPACITORS ).
4 caps = 4 phases, thats right?

So, i need some SMD resisrors for this mod, to solder then on top, but what nominal? Cannot find datasheet...

What comes to vDD mod - try it from pad B-to-ground (VR @ 20x the stock resistance).

Ok! Worx fine
I took 47K, so vDD becomes about 2.22V. Next time i`ll take 100K.

btw, did you try the reverse mods (in post #73)?

Yeap, but just vDDQ.
47K VR makes 1.96V as you said above. Need 100K, or maybe 80K.
Btw, lowering vDDQ lowers overclocking.

Thanks for your help!

[Droperidolum]

So, memory on 1332 MHz, vDD=2.25V, vDDQ=2.05V. Absolutely no artefacts. Default timings.
3DM06 runs 1377 but with arts.
Mem is very hot, maybe i`ll try to make custom mem watercooling.
Tomorrow i go to worrrrk Benches and screens on monday evening.

[largon]

3kΩ SMR / cap you circled would cripple OCP enough to prevent it from bugging you.

[Stelios]

So, memory on 1332 MHz, vDD=2.25V, vDDQ=2.05V. Absolutely no artefacts. Default timings.
3DM06 runs 1377 but with arts.
Mem is very hot, maybe i`ll try to make custom mem watercooling.
Tomorrow i go to worrrrk Benches and screens on monday evening.

What is the trimmer resistance you're using for vdd ??? 47k or you changed it ???
Max resistance for lower vdd ? Right ??

Nice memory clocks !

[Droperidolum]

largon, thank you very much for your help! I`ll try OCP later.

Stelios,

What is the trimmer resistance you're using for vdd ??? 47k or you changed it ???

its little lower than 47K for 2.25V vDD, but i dont know how much exactly.

Max resistance for lower vdd ? Right ??

dont understand

Nice memory clocks !

THX! Working for more

[jackies]

Droperidolum preved!
Do you think you could measure the final resistance of your potentiometers?
I finally received my waterblock, but I dont have any trimpots, and it'd be easy for me just to use regular resistors, if I knew exact values.
Could you help out a russian brother?

Zaranee spasibo!

[Vivi]

Wow very very nice block,

What are your temps?

im sure if you use a regular resistor it'l be fine, but then you wont be able to go higher if you want to , but very nice for 24/7

[jackies]

Yeah that's why I got the block, with stock cooling card was overheating even on windows desktop.
Like, it was hot to touch and produced characteristic smell.
Now temps are around 30, depending on whether I'm running AC or not.
I haven't yet benched it or anything, just putting this system together.
Maybe will post a worklog later on or something...

[Vivi]

cool

im wondering.. is a 9800gtx better than a gts 512 clock for clock? cause when modded the gts can clock higher, and even higher with ln2 / dice
i know the gtx's mems are better, but thats about it

[Droperidolum]

Sorry, have some problems with my Maximus Formula, so pictures and voltage-resistance table will be later if needed.

[Renegade5399]

Bump. I am getting one of these soon and need to know the proper solder points for the memory voltage mods.

[DonNiger]

Pumping aswell - any updates?

[Fusion2002]

What kind of single card 3dmark scores are you guys getting pre/post volt mod?

[DonNiger]

I need your help. Did the vgpu mod, tested it and it worked. I tried to arrange the wires but the one which was connected to that "dot", came off. First I thought that because of a pure soldering but no - that dot came off too


As I expected, my VGA still works but without any drivers installed. Actually, no drivers are recognizing that VGA no more.

Can anybody tell me, where that dot was originally connected and what it was connecting? It is not possible to replace that dot, therefore it needs some wireing if possible.

It might look like a bit offtopic but please do not kill my post this time. It is still part of voltmoding.

[cowie]

^ ow i hate when that happens

i'v done the core mod to my gtx+
same lackluster results as some gtx's only 900/2200 @1.35 on air
but one thing low low low idle/load temps 33c/52c in 68f room no case
load temps come down very fast also

[Vivi]

I need your help. Did the vgpu mod, tested it and it worked. I tried to arrange the wires but the one which was connected to that "dot", came off. First I thought that because of a pure soldering but no - that dot came off too


As I expected, my VGA still works but without any drivers installed. Actually, no drivers are recognizing that VGA no more.

Can anybody tell me, where that dot was originally connected and what it was connecting? It is not possible to replace that dot, therefore it needs some wireing if possible.

It might look like a bit offtopic but please do not kill my post this time. It is still part of voltmoding.

hmm, the removed dot shouldnt be a problem.

[largon]

There might be a PCB via under it.

[Jaan]

I have this card in my hands now, I see this missing dot and I see a part of PCB wire in the hole too.
Problem is, that this point is connected to GND and I don't think this is right..
pic of actual card:

I need to know some other points on pcb that is connected to this "dot" (Vgpu mod point)
It seems that this point in hole is another layer in pcb or smth, and if I connect this to mod point I have max Vgpu instantly.

[aussie-revhead]

Guys , does the info in this thread apply to GTX+ also ? Has anyone tried this on a + ?

OP - near 20k with a dual core is excellent .

[quake6]

So, these four brown caps around primarion is 740 Ohm each (OMG I just measured RESISTANCE of CAPACITORS ).
4 caps = 4 phases, thats right?

So, i need some SMD resisrors for this mod, to solder then on top, but what nominal? Cannot find datasheet...

Anything new about this?

[Eiswolf93]

Hi

can i take a 25k VR for the VDD mod? i dont have any 50/100k here.

is the VDDQ mod now useful or not?

Eiswolf93