Palit 7600GS DDR3 AGP (sonic) Voltmods - done

[V0rt3x]

I made this modding guide because i haven't found the mods postet anywhere else yet, and i think they may be useful.


This mod is for the AGP version of the Palit 7600GS DDR3 (Sonic).
The card overclocks decently with no mods. From the stock 400/1000 i got 560/1620 with no mods, but i felt that the card could do more.

After a close look on card, i found the voltage regulators used for both VGpu and Vmem.
Both are APW7120 300KHz PWM controllers. The VGpu controller is on the lower side of the card, and the VMem controller is in the upper side. I have highlighted their position on the back of the card in the first picture. In the same picture you can find the measure points for both VGpu and VMem.



By default, i had 1.206V for the GPU and 2.08V for the memory.

Let's start.
Looking over the datasheet of the APW7120 i found that the FB pin is pin6, and the GND pin is pin3.
There are more methods of modding:

Pencil method:
For higher VGpu and / or VMem, pencil the highlighted resistors. The more you pencil, the more the voltage increases.



Be sure to measure the voltages from time to time.
I had a reading of 738ohms on the VGpu resistor. Lowering it to 580ohms i got about 1.55V on the GPU, which was enough for a 700MHz GPU frequency.

on my card i need:
1.20V for 550-560MHz
1.30V for 600MHz
1.42V for 650MHz
1.55V for 700-710MHz

As far as the memories are concerned, i had 622ohms on the resistor by default. Lowering it to about 580ohms gave me about 2.23V VMem.

so, i got:
2.10V - 815MHz (x2)
2.15V - 835MHz (x2)
2.2xV - higher clocks but lower score in 3dmark2k3 - even though i get no artifacts :|

A tip for the pencil method. The resistor's surface is too small and for higher voltages you mey need to pencil more,

but there's no free space left on the resistor. You can very well pencil between pins 3 and 6 of the controllers. You can also read the resistor's value by measuring the resistance between these pins.

VR method:
this can also be done in more ways:
-Solder a 10Kohm VR on both ends of the VGpu / VMem resistor
-Solder a 10Kohm VR between pins 3 and 6 of the voltage controllers
-Solder a 10Kohm VR between pin6 on the controller and any ground point on the card

Be sure to set the VR on the max value before soldering it. Lowering the resistance increases the voltages.

This is my score after modding (no tweaks), low RAM clocks.. etc


DISCLAIMER!
V-mods were tested and worked on my card. I am not responsible for any damage that might occur to your cards due to modding.

Happy Modding!

[Erdemliol]

Thanks for the mode

I've got this card and I've managed to clock it 400 1000@ 630 1595 without volt modding. 3dmark 05 scor is 6530. If I have time I will try modding the card

[wertuy]

Hey vortex,
First of all, thanks alot for the guide.
I have a few questions I would like to ask you about the Vmod (probably since I'm a noob at electricity):
First, to measure the voltage, you need to touch the points you showed with the + of the voltmeter but what should you touch with the -?
Second, can you explain a little more specifically about the VR method?
Do you need to do all of the things you mentioned or will 1 of them be enough?
and last 2 questions:
what is a ground point, and which leg(s) will I have to solder on this VR I bought: http://img108.imageshack.us/my.php?i...5021512ka0.jpg

Sorry about all the questions, but as I said, I'm a real noob at this :S

Edit: Oh, and btw, what was your temp at load with the Vmod? Did you keep your stock cooler or switched to a better one?

[DZhon]

So, Who can tell me about temperature, please ? I want to do this Vmod, but only for GPU, because 2.0V - it`s already high for DDR3, In my opinion.

[Console]

So, Who can tell me about temperature, please ? I want to do this Vmod, but only for GPU, because 2.0V - it`s already high for DDR3, In my opinion.

2v for ddr3 isnt really that high most have max Voltage on the data sheets as 2.5v I have mine @ 2.3 on my 7800gt

[DZhon]

I agree, but I didn`t found any datasheets for this memory. And I afraid of high voltages O_o

[DZhon]

So, I received this results:

Vcore - ~1.375 V, 690MHz GPU, Delta -90, but I didn`t try another delta.
Vmem - ~2.2 V, 850 MHz RAM

Temperatures were not high, because I used 2x120mm fans near VGA.
I tryed set more Vcore, but Butterfly test in 3DMark always failed



I found some information about APW7120, which controls voltage and so, it has bug, called in Russia "protection for voltage", this chip usually don`t work with voltages above 1.4 V without special modications

[pobolycwm]

Looking at the listing above for the vr mod, it says I will need 5 10k vr`s, is this correct???. As I am off to Maplins here in the uk in the next few days to stock up on my kit..

Just a quick Q again, Can Ijust do the vgpu and vmem resistors or do i have to do them all.

thanks
Pob

[V0rt3x]

sorry 4 the delay guys.. i hope it's not to late for my answers:

wetury: any of them is enough and works the same

pobolycwm: there is no problem if you do the vmod only for the gpu or for the memory.. they are independent.

as far as memory voltage is concerned, i found the sweet spot at 2.21V - 860MHz. at higher voltage, i get worse results in 3dmark, even with higher clocks

[i found nemo]

viva los turions, hey on everest is ur write speed off by like 2-300 mb/s.