Question New PC build won't turn on ?

[Aiden01]

So i decided to build a pc with some spare parts that I have at home that I know work, After finishing the build I went to go turn the pc on.
And it did but just for a few second without POSTing and turned right off.
I tried turning the pc back on again but nothing seems to happen.

 

[Phillip Corcoran]

Not enough information. Please post full hardware specs of your build, including PSU make, model & age.

 

[Aiden01]

mobo: asrock b150m combo
cpu: i5-6500
psu: evga 500w bronze
ram: crucial 8x2 ddr4

It's decently old, but I know that the psu and ram were working just before making this build.