NU-14s VS NU-12s

Solution
NU-12S won't hang over RAM slots and with it, you have no RAM clearance issues. Though, CPU cooler is 158mm tall,
specs: https://noctua.at/en/products/cpu-cooler-retail/nh-u12s/specification

While NU-14S will overhang over 1st RAM slot. There, you either need to use normal profile RAM which is no taller than 32mm (e.g Corsair Vengeance LPX) or remove the front fan completely. You can move the front fan up a bit to fit 33.5mmm Vengeance LPX under it but it also increases the CPU cooler height from the standard 165mm close to 170mm,
specs: https://noctua.at/en/products/cpu-cooler-retail/nh-u14s/specification

If you don't OC your CPU then NU-12S is more than enough for your CPU.

Aeacus

Titan
Ambassador
NU-12S won't hang over RAM slots and with it, you have no RAM clearance issues. Though, CPU cooler is 158mm tall,
specs: https://noctua.at/en/products/cpu-cooler-retail/nh-u12s/specification

While NU-14S will overhang over 1st RAM slot. There, you either need to use normal profile RAM which is no taller than 32mm (e.g Corsair Vengeance LPX) or remove the front fan completely. You can move the front fan up a bit to fit 33.5mmm Vengeance LPX under it but it also increases the CPU cooler height from the standard 165mm close to 170mm,
specs: https://noctua.at/en/products/cpu-cooler-retail/nh-u14s/specification

If you don't OC your CPU then NU-12S is more than enough for your CPU.
 
Solution