Depends on what you do - one way some gamers and others gauge how much you need is to look at typical prebuilts - whatever they have is generally at the low end as the manufacturers have always been low balling the DRAM in a rig figuring more profit if you upgrade through them, and right now the most common is 6-8GB and many are out with 16GB. Mor3e and faster is the way it's headed, i.e. the DDR4 that's out - if you look through the forums you see tons of folks saying 1600 is all you need, but DDR4 is here, and it starts at 2133, the manufactures have basically just ignored the lower 1866 spec for DDR4, also the 1 and 2GB sticks are gone