Dell Inspiron 620 fails POST, power supply issue

[seasonicpsu]

Hello. I purchased Dell Inspiron 620 full sized tower a few years ago, and haven't upgraded anything save the power supply, graphics card, and memory. A few months back my power supply, a Corsair GS600 failed to start the computer and gave me a blinking Amber light, suggesting there was an issue at POST. At this point I switched out the new power supply for the stock supply that came with the computer, and the computer was able to boot, no issue. I assumed that it was simply a psu failure but now I'm not so sure. I purchased a seasonic M12 II 520 watt modular supply, and when I installed it I'm getting the same issue. Has anybody encountered this issue before or does anyone possibly know what's happening?

 

[Newbbuilder11]

My mentor told me that the PC won't boot if MB, RAM or CPU are faulty