I dont mess with mem clock that much, it makes a small difference. Also, I max out every game too, besides gta (without OC)..I get around 120-200fps on bf4 ultra, but gta iv, if i dont OC, Ill only get around 45-50, with +100 Gpu clock, ill get 60, I sometimes dip 3-4 FPS when im driving at top speed or something.