Why can’t I get my pc to start?

[Dockter]

Case: in win A1 Mobo: ASUS ROG Strix B550-1 Cpu: ryzen 5 3600 GPU: EVGA 1660 XC single fan PSU: integrated power supply 650w 80+ gold Storage: Samsung 970 evo 1tb I started this build a few months ago and have only got it to start a few times out of case, however it doesn’t work everytime I had only got it to bios maybe 2 times and the rest of the time it won’t start I have tested the psu and all connectors replaced the mobo, case, and CPU to no avail. I have tested the power button tried to start ot from the pins and it doesn’t work. I’ve cleared the cmos and swapped for a different SSD. Someone suggested updating the bios but if I have gotten it to the bios before that means it is compatible right? The thing that baffles me is how inconsistent it is there’s no issue I can think of that solves this. I need a second opinion before I throw more money out the window

[Bruce]

what is the memory?
brand of PSU?
can you provide a screen shot of it assembled outside the case, on the ground on a piece of cardboard?
have you tried it without the GPU and plugging the screen into the mobo video port?

[Rustys]

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