Recently I wanna get a new pc so after a few research I did (I cant say I've good knowledge in pc building though, just try to read reviews), so finally i come up with these:

INTEL CORE I5-4690K UNLOCKED FOR OC (4 CORE/4 THREADS/ 3.9GHZ)
ASUS Z97-PRO Gamer
GSKILL TridentX 2x8GB DDR3 2400mhz (CL10)
ASUS GTX970 StriX 4GB DDR5 256Bit
Seasonic X-650
NOCTUA NH-D15 (165MM)
NZXT H440 WINDOW (White)
WD 2TB Caviar Black 7200RPM/64MB (Heavy Duty)
Samsung 850 EVO 250GB

I was then told by the seller that noctua NH-D15 and Gskill TridentX ram will having problem fitting in NZXT H440. The seller actually recommended Cryorig R1 ultimate/universal, said it can be fitted. Tbh Cryorig R1 does look good though. But I prefer Noctua(i used to own one).

Wanna get suggestion from all the gurus here, if there's any other alternative casing I can choose for. or any other suggestion on the build are welcomed too . Thank you very much.

I don't think it's the casing.
Is it the noctua blocking the ram slot instead?