from my experience powerchips dont scale well with high vdimm, unfortunately... if they would, then they could outperform micron chips!
powerchip chips are good for high cas5 and cas4 with low vdimm.
they do scale until higher vdimm than most other chips... but they dont scale much and stop scaling around 2.2v
Ask miravo, hes like a powerchip expert the best batches scale up until 2.3v, some only scale up to 2v iirc.