Specs:
CPU: I5-7600k w/ Hyper evo212
MOBO: Asus Z270-P LGA1151
RAM: gskill aegis DDR4 300mhz 16gb
CASE: Corsair 460x
PSU: Corsair cx650m 650 watts
HDD: western digital 7200rpm 1TB
i put everything together correctly I'm pretty sure , except the hard drive, I didn't put the hard drive in yet. When I turn the computer on, CPU and case fan spins for 5 secs then turns off, and motherboard ram RGB lights are lit. The case had built in stand off's so I don't have to worry about those. I took the cooler off to see if I mis-seated anything but everything looked fine. All these parts are brand new.
what could possibly be wrong