Installed the Core i5-3550 and 2x8GB DDR3-1600. FPS went from 15-25 to 38-50 in the fleet GTN area. Yet to try Warzones, but I'm sure it will run better, since the whole game feels buttersmooth compared to the i3/4GB.
EDIT: It's still quite possible to get FPS down to 25 in case the GTN area at the fleet is really, really crowded (so crowded you can't see anything because of nameplates).
Warzones are 35+ FPS everywhere now though.
Though I still think it's quite disgusting that this game, that hardly looks awesome, runs so slow, while I can play a 64P BF3 game, at the same resolution, with everything on high, at 70+ FPS.