We didn’t find the memory clocks sufficient to catch up with the GPU clocks and therefore decided to do the Vgddr2 voltage modification too.
2.5ns Hynix gDDR2 memory chips. 8 of them give 256MB of video memory for this 7600GS.
For the Vgddr2 modification, we set our eyes on U501.
Like Vgpu, Vgddr2 is controlled by the ISL6549 too.
Again, a 50kOhm potentiometer went between pin 4 and ground of the ISL6549. Decreasing the resistance between pin 4 and ground increases Vgddr2.
As there were no VTT and Vref modifications to be found, the Vgddr2 is believed to be auto-tracking.
Vgddr2, can be measured off either pins of L11.