Pc wont turn on

This has been an ongoing problem for over a week now. My PC has been to 2 shops, and it still won't turn on.

So here's exactly what happened. I had spiderman open, I was afk, PC went to sleep (I thought so anyway) and would not turn back on. All the RGB lights turn on, fans blow, nothing on the screen, and a red led light on the motherboard for the cpu.

So I took it to the first shop, they said it could be the cpu but couldn't test it. So I brought it to a second shop, they said it was my power supply, I went and bought a new one and then he said "oh wait your cpu is bad your psu is fine" so I returned it and bought a new cpu, the technicians said it was working so I took it home and finished assembling it. (Which I've done before) and its still doing the same thing, except this time its a different debug light, for DRAM.

I've reseated the ram multiple times in different slots and tried with each one individually, and no change. I've reset the CMOS twice, the shop tried a BIOS update. Im stumped and I cant keep bringing it to repair shops please help