Why is my PC not turning on?

[Windows Central Question]

Alright, I figured I'd come here because I'm not sure where else to really go. I thought this might be the best place for a stranger to hopefully help solve the problem! So I've had this build for about a year now and everything's, been great up to last month when I was gaming on Valorant and all of a sudden my pc needed to restart every time I was booting up Val. Well, it got to the point where the PC has straight up not turned on in about a month every time I hit the power switch everything flicks on for a split second but nothing starts spinning. I have done everything I could possibly think of, I switched my Motherboard, CPU, RAM, Power Supply, and have tried starting it up without my GPU, tried with no HDD or SSD inserted and still it has simply only flicked lights for a split second at this point and nothing else. The only thing that seemed to make a SLIGHT difference was when I switched from my old to new power supply, my old one nothing would even flick for a second and it was a bronze 500 W and this new one causes things to flick on for that split second and it is a gold 700 so if anybody has any ideas the help would be appreciated!