hi, I changed RAM and HDD to SSD , but after (Avengers) reassemble ,I get 3 bips and it doesnt boot, yeah!

I'm gonna be troubleshooting , and that means doing it all over again.

Having done other models repair, I find the interior design super messy, as parts have barely enough place to get in and out. (power supply, Logic board)

What order of trial would you recommend ? RAM (that would be the longest) ? connections?

Thanks

so, you'd buy a new one !