Just from what i have read higher than 1.4 vtt not good. Plenty of people with this board with 4 gigs of ram linked n synced with p1 p2 enabled, check your everest bandwidth with p1 p2 on auto, no bandwidth at all, have to have p1 p2 enabled. Yes 4 gigs 2x2 is harder, guys here have 8 gigs linked n synced at 1800mgz with p1 p2 enabled, so no problem to do.