VDimm-Mod

Datasheet of the chip:

http://www.semtech.com/pdf/sc2616.pdf

The middle pin of the 100K potentiometer normally would need to be connected to SC2616's Pin #1 (FB). But as the chip has very tiny legs/contacts, that would be nearly impossible to do with normal equipment. Thus we trace pin #1 to a SMD/SMT resistor just next to the chip (marked in the pic). Now you need to connect the potentiometer's middle pin to the side of that resistor, facing the greenish capacitor next to it, as seen in the pic. After that you have to connect the outer pin of the potentiomter to Ground. Just like when doing the VCore-/OVP-Mod, I used an empty solder pad ("EC57") as Ground. Again, it was planned to be used for a cap and was then left empty in the final product (see the pic for details). Measuring point for Vdimm is on the second mosfet from the left, under the RAM slots. Make sure to take a look at the pic for the correct leg, as it depends on how your board is placed on the table. That way, you can't go wrong.

Southbridge-VMod

For that last mod, again a 50K poti is needed. To supply more voltage to the southbridge chipset, it's required to remove the SMD/SMT resistor "R151", next to "VR4" (looking like a mosfet, right next to the second PCI slot, counting from the top). You just desolder that resistor and connect the upper solder-point, which is now empty (after having removed the SMD/SMT resitor), to the middle pin of the 50K potentiometer. Afterwards, you connect the outer pin of the potentiometer to a Ground point nearby. I used the solder-pad ("EC32") next to the battery, right under PCI-slot #3.
The measuring point for the southbridge voltage is the upper contact of the capacitor "EC42", right next to the other soldering-points.