When I went from 3x1gb OCZ on windows XP, to 3x2gb OCZ on windows 7, I had to increase DRAM volts from 1.6 to 1.64 and increase qpi v from 1.31 to 1.35 to achieve stability.

I also had to bump up my vcore by 2 notches, but later confirmed that is because I used linx 64bit with 4-5gb of memory for testing. linx 64 bit using 4-5GB mem required 2 notches higher vcore to run 10 passes stable, vs prime for 14hrs or linx 32 bit (linx 32 bit can use only ~2gb max)