Palit 7600GS DDR3 AGP (sonic) Voltmods - done
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.
http://img58.imageshack.us/img58/719/mod1vcn3.th.jpg
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.
http://img243.imageshack.us/img243/7408/mod2vfb2.th.jpg
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
http://img100.imageshack.us/img100/4894/15kxg2.th.jpg
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!