I have the GTX 560 SE and wanted to overclock it using EVGA Precision X, I've been looking everywhere for a stable Overclock with this, but yet to find one. Also this GPU doesn't have the boost clock and normal clock or w/e its called in Precision X.
GTX 560 SE
Don't mess with the memory until you nail down your core clock. You should also decide how high you are willing to go with voltage and temps so you know when it's time to stop. (I won't go over 1.050v and low 70's temp for a 24/7 overclock)