If you put another fan on the 212, it will definitely protrude into the space for the first if not maybe second ram slot. I have a similar setup and went with GSkill Ares to keep low profile with the ram. It still has a heat spreader, but not one that protrudes upward at all, it would fit anywhere. If you only have 1 fan on the 212 and put it in pull only (other side of socket from ram), then your vengeance isn't a problem. You maybe be able to get by with 2 fans if your board wants you to use memory slots 2 and 4, but then you limit your ability to expand, which defeats the purpose of the extra slots.
UPDATE: So basically what the mod said ^