Hi there,
If I remember correctly most of the Noctua coolers will also cause a problem with the cooler overhanging the RAM slots on the motherboard. I used to use the Noctua NH-D14 and it covered the two closest slots.
But it's not all bad news. With the dominator RAM you can actually remove the heat-sink fins from the top of the module(s) by using an Allen Key (wrench) which I did. This doesn't usually cause any problems but you have to make sure there is good air-flow through the case.
Of course, another option is to watercool the CPU.