I am considering pairing a Noctua NH-D15 with the evga z490 but can't find any info as to whether it might block the primary pci-e slot.  This cooler is 150 mm in total width. So length from the center of cooler to the edge on the pci-e side is 75 mm. The board unfortunately isn't on Noctua's compatibility lists (as in they didn't test for it) and they haven't responded yet to email.
 
Thanks for any help.
 
Edit:
Going through manual but is it listed anywhere how far the first pci-e slot is from the cpu on the board? That would help.

I used the Corsair A500 for now as the EVGA CLC were out of stock on amazon when I Built my rig. 
The A500 is 145mm and there is plenty of room to first slot. I will say if you want to run the 10th gen at boost clocks or O/C for any amount of time, then you may need to switch to water. I just ordered a EVGA 280mm CLC as I kept hitting 90c+ @ 4.9ghz+ on air.
Note that it is fine at stock settings, gaming at 55C but if you run RC20 or longer stress tests it will creep up into 90+.

Nice, if you have time can you post what processor you used and the max ghz and temps?
With A500 I was able to get 4.9 all core but it stabilized too high for me at 92c.
So, now I have a 280mm CLC on the way so I can run it at 5+ ghz and be much cooler for longer lifespan.

MyOdessa
 
I have just purchased Z490 Dark and I also would like to install Noctua NH-D15 with i9-10850.
If it does fit, what orientation did you use, i.e. fans blowing toward the top or toward the back?
Or if anyone else installed cpu air cooler that fits and cools down well, please post make and model number.
Photos would be great.

I can tell you it will not fit with normal orientation, the heatpipes will interfere with the memory slots.  I did just install my D15S onto mine and it fits fine even with the "extended" portion toward the rear IO although I have removed the plastic/metal IO cover but there is enough room I think it would be fine even with that in place.
 
I took a pic focused on the front and back heatpipe so can see how much clearance the D15S has in this setup.
 
https://imgur.com/a/8GbZukn
 
Hope this helps.

MyOdessa
Good to know. Thank you DEJ915.

Sure thing, I actually just reinstalled the plastic cover and it still fits fine.

I've decided to answer my own question: does Noctua NH-D15 fit Z490 Dark with, in my case, G.SKILL TridentZ RGB Series 32GB (2 x 16GB) F4-3600C16D-32GTZR (44mm/1.73" high), and without obstructing first PCI-e x16 lanes slot for a GPU. (because EVGA ****ed up and made second x8 lanes only)
I picked up NH-D15 and DeepCool Assassin III, both are top air coolers and performance wise are roughly the same. According to majority of the tests Assassin III is louder then NH-D15 by about 3db, which is significant because decibels are geometric progression scale, but total is still quiet enough, at least that what I hope for. lol.  Noctua is marginally better made and marginally better quality, it is hard to explain, but it just feel better. On the other hand, NH-D15 is wider and it's radiator sits lower over the slots.
This was just a dry run, I did not removed CPU cover or screwed all parts tightly, so when installed both would sit @2mm lower.
 
NH-D15 will fit EVGA z490 Dark only with fans blowing upwards, with outside fan on top, and even in this configuration I would have to move outside fan to have clearance for my memory. It is impossible to have outside fan on the bottom because it will obstruct PCI-e 1 slot. It is also impossible to fit NH-D15 in any other orientations, because pipes spaced to wide and hit memory and cover. 
Assassin III is narrower then NH-D15 and has more clearance on the bottom over the memory, it is also only will fit in fans blowing upwards orientation, but it clears memory just fine, easy to fit outside fan, it may even fit fan without obstructing PCI-e 1 slot, but air flow will definitely obstructed with fan on the bottom.  I did not though about taking photos until after I started to fit Assassin III, just notice that Noctua is wider, lower and does not fit as well as DeepCool.