I have the cooler in operation on my board, with normal Crucial Ballistix and there is plenty of space to the cooling fins. RAMs with larger coolers or LED lighting will certainly fit. The fans protrude a bit beyond the cooler and you have to look a bit where you mount them. But there you are quite flexible. I only have one fan on the heat sink because one in the back of the case sucks the air out directly.
The cooler comes pretty close to my GTX 970. It doesn't have a backplate, but in terms of space, any graphics card should fit, since they never really build up much on the back.