This would be a good reason to buy DIMMs that don't have gigantic decorative heatsinks attached.
P.S.: You haven't accidentally rotated the CPU cooler 90° from its normal orientation, have you? The fans should be blowing from the front toward the back, not from the bottom toward the top.
They aren't that big, I got them based on the system guide recommendation and price:
However, the RAM slots are really close to the CPU:
No, I checked that the arrows on the fan show it pulling air from the front of the case and blowing it across the CPU towards the back of the case, which matches the airflow of the rest of the fans in the case. I just got too big a cooler for the motherboard.
"In theory, there is no difference between theory and practice. But, in practice, there is."
- Attributed to Jan L.A. van de Snepscheut