Question [HELP] PC Won't Boot

[Sungate]

I started building this today and the only signal I can get is the lights blinking and the fans spinning if I plug in my motherboard connector, but it stops when it's completely in.

 

[rgd1101]

full system spec? include brand and model of the psu

 

[Sungate]

full system spec? include brand and model of the psu

Ryzen 5600x
Radeon 6700xt
MSI Mag B550 Mortar
16 gb 3600 ram
Silverstone Essential 750 watt

 

[Paperdoc]

Not clear what is meant by "it stops when it's completely in."Do you mean the system looks OK if tried outside the case, but will not respond when the mobo and components are mounted in your case?