noctua.at/en/nh-d15s/comp here is the compatibility list from noctua..should be all MB on it

Regarding the I9-9900K (https://ark.intel.com/products... ; 8 cores; TDP = 95W), I see no problem at all. I have been using this cooler for about a year with an I9-7920X (https://ark.intel.com/products...; 12 cores; TDP = 140W) without any problems. Actually, there should still be room for overclocking.

With regard to the space conditions, you have to take a closer look. I use the cooler on an ASUS PRIME X299-A motherboard. I have not experienced any restrictions with regard to RAM (be careful not to use RAM heat sinks that are too high) / PCIe slots.