I think the cooler will fit, but you will probably install the first RAM slot, i.e. you should make sure that the motherboard can also boot with slots 2+4 (instead of 1+3). Besides, logically you will never need all 4 RAM slots.

The Venti can be mounted freely in height on the cooling fins. Then it also works with the large RAM modules. The Dark Rock4 is not as "wide" as the Dark Rock4 Pro and therefore also works with 4 banks.