Gigabyte ga-z77-d3 (rev 1.1) won’t stay on

[Shortyboss21]

Hi I recently went to build a pc and I’m bread boarding it and it turns on then off. But it Varys how long it’s on, sometimes it’s 1 second and sometimes it 39 seconds and I have tried ram, video card, and hard drive and it’s all the same. I came to the conclusion that I think it’s the psu. It’s brand new but it still could be defective. Gonna return it tomorrow and get a new one to see what happens if anybody thinks it’s something else please let me know! 
Pc specs: intel core i5-2500k

gpu: asus gtx 1060 6gb dual

psu: evga 600w 12v 80 bronze

8gb ddr3 1600MHz 

Thanks for any help!