7900GT Voltmod-2

[Shark-357]

For 1.55V u dont need to remove the resistor

[DeToNaToR.cl]

for what voltage do i need to remove the resistor?

[Shark-357]

For anything over 1.55V u need to replace the resistor .

[DeToNaToR.cl]

Thanx

If i remove the resistor and i make this with conductive ink will i get 1,6v?

[Miwo]

Does any "conductive pen" mod work for the 7600GT?

[t024484]

Thanx

If i remove the resistor and i make this with conductive ink will i get 1,6v?

No it won't
Sorry to be a bit brisk, but you should first read before you ask.
All the answers to your questions can be found in this thread.

[Per Hansson]

Would it be any problem to add a 45k ohm resistor in parallell with the 5kohm one to get 50k ohm and thereby switch over to the K8 voltage table?

Same question for increasing the switching frequency of the vreg chip to make it work better at higher frequencies...?

Reason I ask is that I'll be using a dipswitch, and if I could add the resisors in parallell I could also disable them with the flip of a switch ;-)

[***Deimos***]

Would it be any problem to add a 45k ohm resistor in parallell with the 5kohm one to get 50k ohm and thereby switch over to the K8 voltage table?

Same question for increasing the switching frequency of the vreg chip to make it work better at higher frequencies...?

Reason I ask is that I'll be using a dipswitch, and if I could add the resisors in parallell I could also disable them with the flip of a switch ;-)

ahha, lol


45K || 5K = (1/45 + 1/5)^-1 = 4.5K
when you have two resistors in parallel, you will ALWAYS get a total resistance less than the smallest of the two. If both are the same, you get half their value.

I think you confused with resistors in series. However, to put a 45K in series, you would need to cut the traces, or remove some SMD. If you choose the later, then you are doing exactly what the mod suggests.

Increasing the frequency of the voltage regulators might improve stability a little at higher voltages, but typically wont do anything.

If you want to use DIP switch, may I suggest the following [(50K or 5K),(D508 to gnd toggle), (D511 to gnd toggle)]

in addition, you might have to do the over-current protection mod too.

[Per Hansson]

Thnx Deimos, I really did not know that, glad I asked LOL ;-)

Guess I'll only do the D508, D511 and the last unnamed one (0,05v) and be happy (hopefully)

[nib95]

Can someone host a pic of the easiest way to volt mod a 7900 GT to 1.4v (if thats safe with the stock cooler). I'm running SLI so I guess I'd have to do both.

is it true that you can use a pencil to do it?

[***Deimos***]

Can someone host a pic of the easiest way to volt mod a 7900 GT to 1.4v (if thats safe with the stock cooler). I'm running SLI so I guess I'd have to do both.

is it true that you can use a pencil to do it?

Uh huh, sure its 100% true you use pencil to do it.
First, find a pencil.
Second, put it in your hand.
Third, go use mystical magical "thread search" or read previous pages in thread.

You so lazy. -_-

EDIT: Its amazing you have the energy and stamina to make several posts in multiple threads, yet can't seem to be able to read previous pages in those same threads... dude, the link you got from nn__step is from the same thread you posted in!!

[Zenjirou]

i checked radio shack, and homedepot. lol, does anyone know where to get the conductive pen, or where to get online.

[***Deimos***]

car maintanace store. Electrical store. Radio Shack is definetly a good try, but I dont think Home Depot was such a good try.

this is perfect:
http://www.directron.com/conductivepen.html

edit: let google be the sail and wind blows in your hair
http://www.xtremeresources.com/forum...ead.php?t=8106

[taotao0210]

Hi everyone,

i mod it with a silver plate and get v1.4, now i oc my card to 660/1740 ( i am ing) but there is a problem that the temperature is so high. 43° idle and 69 load。i am using a aircooling VF700-alu ( it,s made by ZALMAN). what is the safe temperature? ( i think i will be killed at summer) i can't buy VF900-cu at store in china, should i use a watrcooling? thank you!

[HotFox]

I started a new thread to have a clean start for those who have not followed the previous thread, and to bring things to a final state.
This was possible because I received my 7900GT yesterday, and could do quite some testing to solve some problems that where still there.

The heaviest test I could use was "Comanche 4 Demo Benchmark Test", because with this Benchmark I got black screens long before other benchmarks like 3DMark05 were doing.

Black screens are the prove that the Voltage Regulator, the ISL6568, doesn't "like"something.
This something can be either some sort of voltage protectection, either undervoltage, overvoltage or too much ripple.
It can also be overcurrent in some form.

I could go to 710Mhz on the core with AtiTool without artefacts, but Comanche did not let me get passed the 545Mhz, and gave me black screens above. This was with 1.55Volt Vgpu.

To make a long story short, it was not the overvoltage protection giving me problems, neither was it the overcurrent protection. It turned out to be that with the preset switching frequency, the convertor could not supply enough energy.
This type of "bucket"convertor supplies a packet of energy with each bucket that is tranferred at a clock period. To get more energy, more buckets have to be transferred, and hence the swiching frequency has to go up.

That is exactly what I did, and every benchmark can now run at 710 Mhz with a Vgpu of 1.55Volt.

The picture below shows AtiTool, where you see that it is running for quite some time without artefacts at 710Mhz Core and 1800Mhz Mem.
Temp does not exceed 62C with my ZalmanVF700.

Attachment 45295

All the necessary mods are combined in the next mail, because I did not manage to get everything in this mail!

I think the Voltage Regulator is too hot
When I mod over 1.4V, system always halt in 3dmark03

[DeToNaToR.cl]

For the vmem 2.2v Vr-Zone mod what type of pencil should I use? it says just "pencil"

[alpha0ne]

For the vmem 2.2v Vr-Zone mod what type of pencil should I use? it says just "pencil"

A lead pencil

[Dihon]

My card tops 695, even with 1.6V.
Is it the OCP that causing the problem ?
Cause I haven't done the OCP mod.
The 3K5 ohm should be replace with 6K5, isn't it ?

[HotFox]

My card tops 695, even with 1.6V.
Is it the OCP that causing the problem ?
Cause I haven't done the OCP mod.

I think the missing parts (like capacitor) is the problem.
It make the Voltage Regulator too hot when you mod Vgpu over 1.4V.
So We have to find out which parts are missing.

[SF3D]

HotFox

What kind of cooling you have? I really don't think that heat causes your problems. Voltage regulator doesn't get hot at all, even with 1.6V. Try to increase your PCI-E frequency 100-->105 for example.

[tortiator]

made the secound mod too (1,55) now 691 gpu @ sli !!!!

14.000 3dmark 2005
7500 3dmark 2006

ans single 10840 points with 3dmark2005 ....

thx guys for the mods!

[HotFox]

HotFox

What kind of cooling you have? I really don't think that heat causes your problems. Voltage regulator doesn't get hot at all, even with 1.6V. Try to increase your PCI-E frequency 100-->105 for example.

I'm using the Jacsh1 from Jetart.

[HotFox]

made the secound mod too (1,55) now 691 gpu @ sli !!!!

14.000 3dmark 2005
7500 3dmark 2006

ans single 10840 points with 3dmark2005 ....

thx guys for the mods!

Can you try 3dmark 2003 once?
I always halt when I mod to 1.55V.

[ryankenn]

I have tried to bundle all the wisdom of previous mails in the pictures plus the explaination below.

Attachment 45296
The next picture shows the Mods to change the 1.2 or 1.5 Volt to a higher value.
C gives 0.05 Volt increase when shorted to ground
B gives 0.1 Volt increase to ground and
A gives 0.2 volt increase to ground,
Plus any combination of A, B and C.

Attachment 45297

I have given two possible routes to achieve your Vgpu increase.
Use either the upper or the lower set of traces.
When you only use the red trace, you will have 0.05Volt increase. (1.25V or 1.55Volt)
When you use Red plus Yellow, you will have a 0.15Volt increase (1.35Volt or 1.65Volt)
When you use Red, Yellow plus Purple, you will have a 0.35Volt increase ( 1.55Volt, do not use it in combination with the 50Kohm resistor mod)
Of course you can also connect a single point to get what you want, f.i. ground point C (sorry for the earlier typo) to get 1.4Volt.

I'm planning on using the mod to get 1.55V on my Thermalright V-1 Ultra cooled BFG, but reading through the various posts I just want to verify what I'm seeing/reading.

It seems like the easiest way would be to straight shot the bottom row ( inside my blue box ) to the ground point, but I have yet to see anyone go that way, most loop over the top. Is there a particular reason for this? It looks like the straight line of the bottom route is so much easier.



Second, in the description given, I would believe that connecting the purple line ( Point A ) would give a 0.2V increase, resulting is 1.4V on a previously un modded 7900GT. But this would have me shorting Point A to a point right next to it, AND then to ground. Most of the mods I've seen only go from Point A to ground, and aren't shorting to the pins next to it. I'm assuming it will work either way, just curious. Also you give an example of Shorting a single point to ground, Pt C in for F.I to get 1.4V, but from above, I though that should give only a 0.05V increase. Just a typo?

Here's the route I see the most, and it just straight point A to ground, no shorting to the pin nextdoor.



Thanks,
Ryan

[Dihon]

What kind of cooling you have? I really don't think that heat causes your problems. Voltage regulator doesn't get hot at all, even with 1.6V. Try to increase your PCI-E frequency 100-->105 for example.

I'm using Zalman VF700 & my PCIe frequency is 110, still can't go beyond 695.
What about OVP, is it really not exist for 79GT ??