I was only able to mod the core voltage. Even with a magnifying glass my eyes were not good enough to sodder a wire for memory voltage. I killed my first card (lucky they are cheap), but managed to mod the second ok.
x99-pro/3.1 | i7-5820k | 16gb gskils 3000 | Nvidia gtx 980 ti | 512gb SM950 Pro | Predator 360 AIO | ASUS PA248Q | Seasonic Platnium 1000w