I've almost completed a build with the two above components (and an i5 4690K, ASUS 980 OC, a decent PSU, an SSD and a 2TB HDD) but have hit a stumbling block. Despite PCPartpicker assuring me a Noctua NH-U14S would fit, it doesn't. The heatsink fouls the Impact Power 2 riser, which means I can't secure it.

So my question is, I'd rather not rely on the stock cooler, can anyone who's built something with the Maximus VII recommend a decent heatsink?

Thanks in advance