The legendary NH-D14 is now discontinued but is not impossible to find. Check out these two identical passively-cooled builds featuring the old flagship Noctua cooler, Intel's i3-8100, a Seasonic-made LDLC PSU, and Lian-Li's PC-Q10 case (with mesh on top and bottom). It's a tight fit, but it works.
In most scenarios, titans like the NH-D14, Phanteks PH-TC14PE, or Thermalright Le Grand Macho will perform better in passive mode than smaller coolers advertised as fanless like Arctic Alpine series or Nofan CR-80EH.
